My take is somewhere between @Nitenman's and @nameless ronin's. The clans are clearly nations under an empire, and always at cold-war or so, but also currying favor with the empire, and cooperating grudgingly at best, at least post 1000 IC.
The families are generally cooperative within the clans, but also generally not fully in accord, either. The amount of plotting and scheming between them varies - the Crab simply argue it out, or go to a sumo match or warriors duel, to solve internal disputes. The Crane generally talk it out; each has their field, and deference to specialization generally carries it; when it doesn't, champions resolve it. The Dragon rely upon meditation and compromise. Daimyō and Gokenin hold while they are profitable, and are encouraged to retire or "promoted" to court functionary if they don't pay the taxes and maintain the requisite troops. Each holds from his family, not from the clan; the clan can remove (by promotion, banishment, or call to monasticism) but not dictate appointment of replacement - the family daimyō does. If the clan sees recurrent failures, the family may be deprived of the holding and it assigned elsewhere - but it's done as a "public acknowledgement of a gift.
 

The full story is that Doju Hayaku (the founder of the Daidoji) pretty much wrecked the Shadowlands all by his lonesome while looking for his sister. He could only find her sword tho, in the Temple of the Thunders, but then he ran into an ex-Hida woman who was banished from the Crab Clan for dabbling with maho (I joke you not here). Enlisting the help of this woman, Hayaku cut his throat with his sister's sword - he died there and his soul was sent to Jigoku by the sword, after her sister's. There, he freed Konishiko's soul and sent her back to Tengoku, then got himself resurrected by the Hida woman. His hair turned white because of the journey to Jigoku and back (yes, it was implied that it was some Taint on him). He returned to the Crane Clan, married the Hida chick, and founded the Daidoji family. This is why the Daidoji is so tough: they have some Hida-like blood too in their veins. 
By the way, Hayaku couldn't save all of Konishiko: what remained from his sister later emerged from Jigoku as the demonic creature called the Dark Daughter of Fu Leng. IIRC there was an abandoned story arc with this, but I'm not so sure about it. 

Why do Cranes have white hair.
The story goes that on the first day of thunder when the champions of each of the clans went with Shinsei to defeat fu leng in the shadowlands, doji's daughter was left behind in the battle, presumed dead. Her other son volunteered to venture into the shadowlands alone to find his sister. When he returned he looked like he had seen horrors beyond imagining, his hair used to be jet black but was now snow white from the things he had seen and he had lost the ability to speak. He did not return with his sister but returned with the ancestral sword of the crane that she carried with her into battle. For his bravery, Doji titled him “Daidoji” or “defender of the doji” and thus the daidoji family of the Crane was founded. The Crane dye their hair white in remembrance of the founding daidoji and also for the distinguishing look it gives them which could be an advantage in many of their dealings with other (or disadvantage at times).

Good point. I think internal family strife may happen too. Without going to full clan civil war, a Daidoji major Daimyo may allow two of his vassals to settle a dispute by an authorized war, and courtier may plead their cause to higher crane leadership to allow two Daidoji families who hate each others guts to pursue blood feud. 
 
Back on the dueling topic, I'd say Iaijutsu should be expected, but maybe not granted. 
If an honor challenge is thrown, nothing should "force" it to be a Iaijutsu duel. Nothing except court maneuvers that would stress out how dishonourable it would be to break from tradition and refuse to fight in the time honoured Iaijutsu stance, sort of bullying the opposing party in using Iaijutsu. And if Iaijutsu is refused, gossip time! Even if victorious, the non Iaijutsu practitioner might get badmouthed and his victory downplayed in court. 
The error would be to think that iaijutsu honor duel is about a skill contest between two honorable warriors. Iaijutsu honor duel is a political tool amongst an arsenal of means to pressure the opponent. And despite the Crane being on top of it, it's a tool also used by other political clans, like phenix and scorpion. 

While I can see that you are adamant at rationalizing the lore and setting of the game to encompass what you are most comfortable with, which systems perfectly allow and encourage.  I can't help but interject when precedence that contradicts cannon is toss out with zero fact checking.
Both in descriptions of forging swords, to use of kiho, and even cooking in rokugan Kami aka the elements are present. It is explained in various sources that everything both people, the ground, weapons, and gods are comprised of the elements. The difference is wether they are awakened or not, hence shugenja's abilities. As well what influence they are under.
Kiho is the conscious manipulation of a persons elements in a unusual way the allows the user to make one element more dominant in there form than others and create the desired effect.    Same goes for forging armor or katanas for a Kaiu.  Its established that a devote enough individual can awaken the kami in any object if enough of their self and spirit is put into it through work and varied conditions. This timeframe varies but in l5r is consistent.
Even every mortal with void that isnt spiritually disrupted dreams magically as the realm of yume-do where rat gods, spirit tapirs, and other creatures occur are a regular thing for rokugani whether they know it or not.
 
At this point it sounds like your trying to convince yourself more than anyone else.  So if you want to use a different term than magic and play without the fantasy foundation the setting is based on your free to.  But if your trying to convince others the setting and game are more like your desired setting than not then I'm going to have to kindly ask you to take a step back and rexamine what you are doing because denial is alot more obvious from the outside.

See you say you have it all and read it all but only quote the mechanics and breifest descriptions of school techniques to me.
It makes sense that you wouldn't concern yourself with any material that further depicts the very same same things your discussing in greater detail when they work against your own arguement.
My claims come from having read the entirety of 4th editions content. Much of what people consider "fluff", a term I vehemently dislike due its dismissiveness, from source books are wriiten in great detail to flush out and provide context and intimate breakdowns of a slew of things in the system. Much of which is ideal for framing a detailed campaign or provided players who care about the substance around and behind their characters to better portray an in depth roleplay.
Book of Earth and Fire as well as Great Clans of forth editions go into detail about gear composition and how Kaiu traditions and smithing methods contribute to their fantastical boost and Kaiu Blade.
If you take the extra step and apply the logic of the nature and magic sections of the same element themed books and how the synergiest structure of kami and ningen-do, the realm of form, bring about rokugan as we know it you might begin to understand why I claim such "delusional" ideas.

You have put into sharp relief why I think this feels generic.  If all samurai are from a single homogenous country, all doing iaijutsu duels, using the same techniques in those duels... well that feels just very generic to me, even if they wear different colored clothing.  You may PREFER generic.  And if you do... well I really can't change your mind on that.  As to an overarching Rokugani culture... well we already have that without iaijutsu... because we still have honor duels as a thing.  We still have bushido as a thing, as well as Fortunism and the Tao of Shinsei as a thing.  There are many cultural ties that bind everyone together... requiring everyone to use the crane's signature style seems extraneous. 

I dislike real world examples to try and show how things should work in Rokugan, because you are dealing with a world that has magic being performed by the descendants of literal gods, but this one works, I think.  I don't know how familiar you are with the cuisine of China, but it is VASTLY different as you travel through different parts.  In the center you have Shaanxi cuisine (or Xi'an named after the central city) With their broad and thick Biangbiang noodles, Paomo, a lamb soup with torn bits of bread soaked into the broth, and crunchy roujimao stuffed with chopped tender pork, chilis, cilantro, and spices.  Then to the West, you have the mostly halal cuisine of the Xinjian province, with skewers of lamb kawaplar resplendent in cumin, Uyghur mutton pilaf called polu, and Pamirden, which is a pie similar to Naan stuffed with meat and vegetables.  In the east you have Jiangsu and Shanghai, with soup-filled xiaolongbao and the cured ham flavored Kou San Si soup.  To homogenize all of them into the umbrella of "Chinese food" and consider them all to eat the same thing causes one to lose all the wonderful and varied cultural differences they have. They have many more differences than just a few different dishes that high levels chefs might make.  The basic fundamentals are different and there is different thought process to the dish.

I bring up the need to showcase cultural differences because Rokugan is a feudal state.  The clans have declared allegiance to the Hantei, but the military power lies within them, not the Emperor.  And these warring clans are very different in culture... which is one of the reasons they can't get along.  THere are Lion who see the Crane as SO different that they want to kill them all.  Now, most GMs won't showcase the different foods that different provinces of Rokugan might have to show cultural differences... most games are going to be based on fighting.  If it would be a shame that for all court games that you have all samurai doing the same thing, with the same techniques, just in different colored kimonos.  This is why it is important to showcase how each clan is different in ways they will likely interact with each other... which includes honor duels.

I feel that the only reason to keep all honor duels as iaijutsu duels is that earlier editions did.  The mechanics for the  new duels are very similar to the opening duel of Kyūzō in "The Seven Samurai", where they study each other, changing stance several times each until one screams and charges allowing Kyūzō to dispatch him with a masterful rising cut from low stance.  So if you like everyone using iaijutsu because that is how it is done in previous editions... well, that just seems more like a dislike of change more than anything else.  If so, I doubt I will change you mind, but I hope you will  consider that a non-homogenous Rokugan is an exciting vibrant place, where a homogenous Rokugan is a much more placid.  

My entire game plan re: basic setting information is to point new players at a selection of sections from Emerald Empire.

You're correct, I'm just saying I think the limit (if there is to be one in a particular context) should be based on the narrative limit of how effective your assistance is.  This is easy to houserule, but it could be an explict part of the game.  The assist rule itself isn't broken fundamentally IMO, they just need to acknowledge it's limitations in some form, even if that's as simple as needing the GM to okay your assist in the narrative.

They get 4th edition mention in Emerald Empire & Secrets Of The Empire (probably more, too).
 

As I said in the thread @Doji Meshou linked, Rituals do not need to be just Theology Rituals.
Tea Ceremony and Hyakumonogatari Kaidankai(Gathering of 100 Ghost Stories) would work well as Aesthetic and Composition Rituals with appropriate effects.
Crafting special items can also be locked behind certain Rituals. Kakita and Kaiu Blades could easily be locked behind Smithing rituals.
Special military drills can also be Rituals.
Rituals do not only need to be Magic.

Heimin and Burakumin men would wear very simple cheap garb that could be dirtied by their activities. Kimono would be only for festivals (not even sure Eta could afford a kimono)
Good idea is to showcase art from the previous and current card game.
For example an Heimin
https://goo.gl/images/bZTej4
Eta
https://goo.gl/images/eMH7CM
One striking thing with Eta and Heimin is the display of skin and tan. Traditional samurai culture shuns the display of skin and tan is the mark of laborers. 
Cultures that care differently about skin taboo are the Dragon, tattoos and their display being an important part of their culture, Mantis who favours practical clothing at sea and sometimes crab in some depictions. 
Dragon monk tattooing
https://goo.gl/images/32Tch9
Mantis samurai
https://goo.gl/images/hmpXYb
Crab ruling family displaying skin shamelessly
https://goo.gl/images/c8vRaf
Political clans may use display of skin as a courtly seduction tool, the Scorpion may range from subtle to provocative while the Crane being more traditional may use it to tease lightly 
Scorpion subtle
https://goo.gl/images/gaZFRR
Scorpion provocative
https://goo.gl/images/obQRPf
crane teasing
https://goo.gl/images/ndwopx
may be noted that some Matsu warriors may sometimes be depicted as showing skin while wearing armour. 
https://goo.gl/images/BrYwnt
but be careful, sometimes the art is a bit absurd
https://goo.gl/images/JKeomT
Shugenja of the phenix and monks closer to nature are also known for displaying skin sometimes
https://goo.gl/images/QeD3dY
Unicorn is probably the clan that should have the less taboo on skin display. They are naturally lightly tanned, they wear leather and fur, eat red meat, have dwelt in the burning sands... But curiously, art shows not much skin display beyond the arms naked with armor classic as they favor heavy clothing and riding gear. 

Display of skin and choose of an attire is interesting in Rokugan as it's one of the few area of personnal expression that a samurai has in an otherwise very uniform culture marked by ancestry and tradition. 
Food wise I'd say it would deserves its own thread. The 4th ed Great Clans sourcebook contains information on food customs. We learn for example an that scorpion are gourmets liking to prepare Fugu, and that Dragon sometimes bypass the meat taboo and consume Goat meat, that they call "Mountain Tuna"

At first i thought it was just similar name due to the dragon clan lands being mostly mountains but then i found their tradition.   To summarize:
"These monks focused on a relationship with the natural world, as only through experiencing the interplay of the elements in their most primal state could the soul be set free. [2] Most yamabushi sects organized themselves into bands of five, with one monk in each band embodying one of the Five Rings. [3]"
While this is from 2nd and 3rd edition sources their philosophies fit in nicely with the kannushi and yamabushi described above.  And seeing as they are recognized as one of the largest brotherhood sects on rokugan and count the order of the seven thunders amongst them I see little reason they couldnt already cannonically exist within the new l5r.

While it is a school I loved since the death preist didnt emerge as an accepted religious sect in rokugan until Tein Shin Yin Wang were made fortunes in the 1160s then the timeline reset would have them nonexistent in rokugan so far.
That said between the techniques of the kuni witch hunters and toritaka exorcist perhaps even yogo wardmasters mechanics and premise for onmyouji could easily be flushed out.   Their are also mechanics in fourth edition homebrew called Court of the Minor Clans that has a Obake minor clan that is very similar to an onymouji you described.
 

On shugenja - the kanji 修験者 (for shugenja) translate as "examinees" (修験 shugen test/trial, 者 sha person) and as "mountaineering ascetic"... a wonderful pun on shugenja and their training...
Yamabushi 山伏 "mountain priest". (山 yama mountain; 伏 fuku lying down, facing down) - note the transition of the second kanji to a wholly different sound - almost literally "lying on the mountain"...
As for shrines without attendants - the only ones I've encountered in the material are those in samurai homes - ancestor shrines. Whether any given GM has upheld that bit is more flexible, but I, as a GM, make it a point that every shrine has one of the following attending: A shgenja, A monk of shinsei, a retired samurai turned clan-monk, or a peasant kannushi. Only that last isn't supported by the materials in 2E and/or 3E. I will admit, however, to not having read most of 4E, and having missed some parts of 2E and a few parts of 3E.
It is important to remember that Rokugan is not Japan, and the syncretic behavior of Japan embraces 3 major religions in varying but non-exclusive proportions: Shintō, Buddhism, and  ancestor worship, with doses of Taoism tossed into all three (tho least so into Shintō). L5R has always intentionally merged those 4 into one syncretic whole. Separating them again does little benefit, and serves mostly to confuse gaijin, most of whom are used to relatively low syncretism in the major faiths of the west.
 

Here is a rahter long topic about L5R and how it would be possible to integrate additional historical Japanese aspects into the LCG, RPG, and Story. Several of the things included are; Yamabushi, Onmyouji, and Shinto Shrines (called Jinja in Japanese). I will provide further details in regards to each of those, as well as links to various sites that you may find useful. In addition I will discuss the Mantis Clan, and aspects about them and the historical connotations from Japan that may fit well for them. I have been studying Japanese culture and religion for a couple years now, and I am blessed to have had to opportunity to visit Japan with regular visits thanks to my in-laws being Japanese.   Yamabushi follow a religion called Shugen-do which is a syncretic faith of Shinto, Buddhism, and Toaism (this is similar in many ways to the design of the L5R combined faith of Shintao). It is a mountain faith that focuses on using asceticism to gain magical powers against evil spirits. This would be a fitting way for Shugenja in L5R to fit neatly within the Dragon Clan, mixing the Ascetic ways of the Togashi Monks with the Shugenja techniques and traditions often utilized by the other clans.  In addition with the focus being on the defeat of evil spirits they would be useful against potential shadowland corruptive forces ,or for calming down angry Kami that inhabit the mountains and/or storms. In fact the religion of Shugen-do is likely the inspiration of Shugenja in L5R to an extent, as most Shugenja utilize some of the concepts to a limited degree. Albeit the Shugenja more likely fill the role of Kannushi in Shinto, more on that later. Links: https://www.japantimes.co.jp/life/2017/10/13/travel/yamabushi-japans-ancient-tradition-mountain-ascetics-opens-public/#.WfuXLGhSzb0
https://www.britannica.com/topic/Shugen-do#ref101681
https://en.wikipedia.org/wiki/Shugend%C5%8D
http://www.onmarkproductions.com/html/shugendou.html
http://eos.kokugakuin.ac.jp/modules/xwords/entry.php?entryID=830   Onmyouji would be a huge boon to the Imperial Families as their own unique take on the role of the Shugenja and how to best serve the Emperor. The Five Elements that L5R utilizes are the same that the Onmyouji use in their magic (again likely a major inspiration for aspects of the Shugenja). Fortune-telling and the reading of auspicious signs for the Emperor would be a key aspect of them, in essence they would know potential aspects of the future (in game turns, perhaps adjusting dials after the fact). They would also be able to fight and put to rest angry dead, something that the Maho-Tsukai (Blood Magic users in L5R) would have reason to fear. Finally Onmyouji were known for the creation of Shikigami, basically creating a body for a Kami to serve you in various dangerous matters, be it spying, guarding, etc. This could be done in game through the creation of tokens for fate cost or something similar. Having the Onmyouji be directly connected to the Imperial Families would also add some much needed depth to the usually antagonistic Imperial Families in a more positive (potentially) light. Links: https://en.wikipedia.org/wiki/Onmy%C5%8Dd%C5%8D
http://eos.kokugakuin.ac.jp/modules/xwords/entry.php?entryID=828
https://en.wikipedia.org/wiki/Shikigami
  Shinto Shrines and thus Shrines in L5R are integral to the community for a variety of reasons. Primarily in that they are one of the few things that brings together peasants and Samurai. Matsuri and various festivals are typically held by Shinto Shrines to instill community values and ideals to all people involved. They celebrate many things, be it the departed, a good harvest, graduations (Gempekku for L5R), reaching adulthood, and Holidays related to various Kami. Shinto Shrines also act as a sort of nature preserve within communities, with the nature being seen as sacred nature. In addition communities often built up around shrines, and the shrines often have a good amount of natural space around them, really creating the separation of mundane from sacred. The Torii gate is integral to the Shrine, and is not just an aesthetic choice, a Torii gate represents the entrance into sacred space, or entrance to the approach to the shrine. When you see pictures of Torii Gates within cities what you are seeing in the loss of Shrine land to the city, with the approach still remaining, not a random Torii being placed without reason. In the time period of L5R, when cities are much smaller, you would only see Torii where Shrine lands start. Links: https://en.wikipedia.org/wiki/Shinto_shrine
http://www.jinjahoncho.or.jp/en/faq/
http://eos.kokugakuin.ac.jp/modules/xwords/entry.php?entryID=248
http://eos.kokugakuin.ac.jp/modules/xwords/   Kannushi are the priests of Kami, and the keepers of Shrines. Within L5R that role is filled by the Shugenja, and very rarely do we see them doing this duty, often leaving Shrines abandoned or alone. A shrine without a priest, especially one with a sacred object to the Kami would likely lead to an angry Kami. With L5R I would love to see the more priestly aspects of the Shugenja explored, overseeing the rituals for Matsuri, doing rituals for good crop yields and bountiful harvests, really having them integrated into the spiitual core of the setting insteado being wizards and sorcerers. Shugenja should feel like they are serving the Kami (and specific Kami), when they go to war they are doing the will of the Kami, but it should be rare for them to go to war. More often they should be giving blessing to the warriors, and speaking on behalf of the Kami in court. This could make them a dangerous political powerhouse (as the Phoenix are looking to be). Links:  https://en.wikipedia.org/wiki/Kannushi
http://www.onmarkproductions.com/html/shinto-priesthood.html
http://eos.kokugakuin.ac.jp/modules/xwords/entry.php?entryID=1285
  Ok now onto the Mantis Clan and my thoughts on them, their culture, and what makes them interesting. A lot of what I will be discussing is generalized from the old L5R with some personal thoughts. The Mantis clan in the old L5R originates from the heir of the Crab clan (Child of the Champion, and a Matsu) who was passed over for his sibling who was a bastard born of peasant stock. His mother left with him and their followers to the island of Silk and Spice. The founder of the clan utilized a Kusari-Gama as their primary weapon instead of a Katana. Looking at this we can quickly see how the Mantis clan would care little for the Katana, first due to their founder, second due to their terrain, and third due to their life upon the sea. The Mantis Clan in the old L5R near the end had an interesting theme of dual wielding peasant weapons, and a long history of using the Kama. The Kama is a cheap weapon, typically used by peasants for farming, so losing it is no big deal. It is also useful on a ship in that if can be used similar to a pick to stab into the wood to keep from going overboard. Finally it is useful in that it makes the wielder appear to look like a Praying Mantis. It is a beautiful weapon for theme, and story. The Fighting style for it would also be based around Eskrima, the Philippine Martial Art (which works for the Islands of Silk and Spice). This would give them a unique way of fighting that separates them from the other families.
Links: https://en.wikipedia.org/wiki/Kama_(weapon)
https://en.wikipedia.org/wiki/Arnis
http://blackbeltmag.com/daily/traditional-martial-arts-training/escrima/10-things-you-probably-didnt-know-about-the-filipino-martial-arts/   Gunpowder and Guns are probably a touchy topic for many L5R players, but I think it is an important thing to broach. Historically the Japanese were using Firearms since the 16th Century (which is around the time Samurai were a major thing). Firearms were introduced by the Portuguese and were quickly replicated by the Japanese. Samurai would lead armies of Ashigaru who would wield the Flintlock rifles of the days. An example of a major Samurai Daimyo who used it to great affect is Oda Nobunaga who nearly unified Japan before one of his own men assassinated him in a Temple (there are reports Nobunaga burnt the temple down and committed Sepuku so his traitorous retainer wouldn't have the pleasure of killing him). Gunpowder could still be fairly controlled by the samurai, without the use of cannons and expensive, but it could easily have its place in the new L5R, really setting the world apart from the previous incarnation. Links: https://en.wikipedia.org/wiki/Firearms_of_Japan
https://en.wikipedia.org/wiki/Oda_Nobunaga
https://www.samurai-archives.com/nobunaga.html
  I think that is a majority of what I wanted to discuss at the moment, and I think you for taking the time to read it. I would love your feedback, questions, and thoughts regarding these questions. I look forward to seeing where L5R goes from here, and I hope that I have been in some form useful.

At the same time, I think it's not unreasonable that if the situation is bad enough that the player essentially suffers an outburst twice over, there should be a pretty serious consequence, as it's a pretty serious thing to have happened.

While I can see that you are adamant at rationalizing the lore and setting of the game to encompass what you are most comfortable with, which systems perfectly allow and encourage.  I can't help but interject when precedence that contradicts cannon is toss out with zero fact checking.
Both in descriptions of forging swords, to use of kiho, and even cooking in rokugan Kami aka the elements are present. It is explained in various sources that everything both people, the ground, weapons, and gods are comprised of the elements. The difference is wether they are awakened or not, hence shugenja's abilities. As well what influence they are under.
Kiho is the conscious manipulation of a persons elements in a unusual way the allows the user to make one element more dominant in there form than others and create the desired effect.    Same goes for forging armor or katanas for a Kaiu.  Its established that a devote enough individual can awaken the kami in any object if enough of their self and spirit is put into it through work and varied conditions. This timeframe varies but in l5r is consistent.
Even every mortal with void that isnt spiritually disrupted dreams magically as the realm of yume-do where rat gods, spirit tapirs, and other creatures occur are a regular thing for rokugani whether they know it or not.
 
At this point it sounds like your trying to convince yourself more than anyone else.  So if you want to use a different term than magic and play without the fantasy foundation the setting is based on your free to.  But if your trying to convince others the setting and game are more like your desired setting than not then I'm going to have to kindly ask you to take a step back and rexamine what you are doing because denial is alot more obvious from the outside.

I think that by design the strife should continue due to the fact that their are various abilities and techniques that utilize strife of a target and would also reflect on how difficult it is to recover strife from the incident that strung you out.
Being emotionally compromised after unmasking while possible i believe is less likely due to the design of all conflicts resolving fairly quickly in retrospect.  So unless the player is getting gang banged by schemes and opportunities i think the concern is lessened.

Exactly this. As noted above, I've no problem with semi-mystical abilities like "pray for guidance and get a vague answer", as long as samurai aren't throwing fireballs.
High level school abilities verging on the mystical is not an issue; Strike With No Though already pretty much turns you into a Katana-wielding nightcrawler, for example.

I think it's not "magic" for everyone, but "mysticism" for everyone. And rituals are a perfect word for the most simple of the many mystical ways things work in Rokugan, that should be accessible to all the ruling class with classical and religious education like the samurai caste. 
And Kihos are mystical, so is the relationship between shugenja and Kami and the quasi supernatural abilities developed by highest ranked of a bushi school. 
There is no spoon... Sorry there is not really magic things. Everything is steeped deeply in mysticism and religion. A samurai doesn't take a ritual to wield magic but to honor his ancestors or pray the celestial order. They should mostly be taken by pious samurai. 
In Rokugan what is actually considered magic is maho, sorcery from jigoku.
 

Many excellent points here on all sides, but something I haven't seen accounted for, unless someone brought it up much earlier, is that in most combat in the new system PCs will be fighting minions, something that didnt exist in l5r til now. 
Considering that criting on minions before passing damage does fatigue equal to lethality and minions only have to have a severity of 7 before they die i feel that allows both razor-edged and heavy weapon camps the abilty to dish out on more even ground.
Now while that doesnt extend to adversaries i like a little meat on their bones. They die too quickly and what was the point? 
And pc vs pc doesnt arise too often in my games but thats what duels are for right? 

I asked my DM after our last session if I could wield my Chokuto in exclusively my left hand and get ambidextrous bonus on every attack because i'm using my offhand. His bewildered silence leads me to believe that's not the case.

Regardless, I for one am kind of glad that the Katana isn't the end all be all greatest weapon. Your sword in war-times is supposed to be a sidearm to a better weapon, like a polearm or zanbatou if you're feeling particularly shonen. Staves doing gratuitous amounts of damage aside, It was always my assumption that the trade off was if you walk into a town with a Katana on your waist no one bats an eye but if you walk into a (non-crab) town with a otsuchi slung over your shoulder or armor strapped to your chest that you were going to be assumed a hostile invader and met accordingly. Why would you wear war gear into town if you weren't going to war with them, after all. Swords are good for what they're meant for, the ceremonial duel, they are a ceremonial weapon, more symbolic than practical on a battlefield. Not to say you can't be the cult-of-swords guy who charges at the army with just his grandfathers blade, but you better be a supremely skilled swordsman, because being poked to death by a naginata or bashed away by a tetsubo is much more likely an end result, and for good reason.

For warfare, they preferred bow and spear. Those were the go-to choices. The katana was, in mass combat, largely a sidearm. 
Whether that’s the intent for L5R in this edition as well is up for debate, but I seem to see more mention of weapons other than the daisho in the starting outfits than in previous editions and things like razor-edged and ceremonial appear to incentivize using wargear (that term alone is indicative too) for war and the katana for other situations.

Honestly, I feel weapons like a tetsubo, naginata and no-dachi are fine doing more damage than a katana. The weapons described as wargear are weapons of warfare. 
I'm not ok with the flimsy armor samurai wear breaking katanas though. It's a rule I would likely ignore in its current state.
That being said, I find it perfectly reasonable for shadowlands creatures and other mythic beings to have hides tough enough to break katanas.
The current rules do a pretty decent job of representing the katana as an elegant weapon which requires skill to use.
The samurai didn't pick the most effective weapon to carry, they picked the most elegant and the one requiring a great deal of skill and mastery.