I don't have any particular characters that I'm super attached to or anything, so there's not a lot I can add there. Awesome to hear you're working on a beginner adventure though, if you feel up to sharing please let the people in this thread know when you're done, it'd be a really handy resource.
Scroll up a few posts 😛 It's very much in the works. Grey Knights too!
This is a pretty solid suggestion, although one thing I'm wary of is creating mechanics around needing to acquire cybernetics, as the way Chambers Militant characters acquire cybernetics is a lot more limited than the mechanics typical characters use. As Chambers Militant characters don't really have much in the way of a standard system to acquire gear (no money, all their gear is "on loan" from their parent organisation and can be swapped out between missions), I've moved to having them acquire cybernetics via a ranked talent (replacement limbs and etc for injuries are free though, naturally). So putting Iron Hands characters in the position of needing new cybernetics to offset their penalties feels pretty brutally punishing. 
What I ended up going with was leaning into their tendency to judge others as harshly as they judge themselves, which often leads to them being aloof ***** who see everyone else as inferior (while also somehow seeing themselves as inferior, they seem like a healthy bunch!), so I went with this;

And on the note of 9e, one thing I had been thinking about is dumping the distinction between Primaris and Firstborn careers, and just having more generalist careers that address the common themes. Like, both have generic bolter-wielding troops (Tacticals and Intercessors), both have forces who focus on melee with light weapons (Assaults Marines and Assault Intercessors), both have heavy weapons troops (Hellblasters and Devestators), etc. Would be easy enough to make general careers, which would be more in line with what the core book does anyway.

One other thing I've been thinking about career wise, is that as it stands Apothecaries, Chaplains and Tech-Marines get some exclusive gear, and the other careers get nothing. I'm wondering if it'd be worth giving each career a nice little exclusive bonus to offset this (something equivalent to a Tier 2 or 3 talent, nothing too good). Normally I'm against this in Genesys as I like how open ended things are, but when some careers inherently have access to exclusive stuff due to the fluff, it might help to even the scales a bit. 

Hey everyone, here's the work I've done on the Chambers Militant Armoury chapter so far. 
https://drive.google.com/file/d/1Yoq2zch0FxeouRIoeSDWovRkwYZPMioL/view?usp=sharing
What's done:
Rules for acquiring gear as Chambers Militant characters (they don't use typical Thrones or Influence). All ranged weapons for Sororitas, Grey Knights and Deathwatch. All melee weapons for Sororitas, Grey Knights and Deathwatch. All armour and forcefields for Sororitas, Grey Knights and Deathwatch. Armour attachments (I may add a few more of these so the formatting isn't finalised) What's not done:
Ammunition rules, including custom ammo. Grenades and explosives. Weapon attachments. General wargear. Familiars and servitors. Cybernetics. Let me know if anything seems missing or incorrect!
Update: It's all done! Whole armoury chapter should be ready to go, let me know if you notice any glaring omissions. 

With the FFG forums due to shut down in a matter of weeks, I have begun to move my updates over to Wordpress.
Please follow or bookmark https://dhgenesys.wordpress.com/ if you want to keep up to date with future updates to this project!
 
 

- Third Edition Core Rules Link - 3.1 Update -
- Form Fillable Character Sheet PDF (Newly updated!) -
- Form Fillable Character Sheet PDF (Old version, only 3 pages instead of five which might suit some people better) -
- Russian translated Character Sheet PDF (all credit to LelouchVee, based on the old sheet) -
- Printer Friendly Character Sheet PDF (based on the old sheet) -
- Rolling Changelog (This changelog starts from the 3.0 release, see the bottom of this post for historic changes) -
- Rules currently at release 3.1 -
This conversion, totalling in at 295 pages of content, brings all the rules you need to run FFG's well-loved Warhammer 40,000 RPG in the Genesys system. Featuring a few new gameplay systems to model the work of the Imperial Inquisition more closely, it should have all the content you need to run a campaign scaled anywhere from dirt-poor Acolytes scrabbling to survive, to all-powerful agents of the Inquisition who condemn worlds to destruction with a quill-stroke. 
The third edition release is a total layout overhaul, redesigning the layout and visuals of basically every page. It's not just visual tweaks; the text has also been expanded and tweaked to make for a better read and hopefully a better gameplay experience. As well, content has been added and tweaked, expanding character options and adjusting some odd balance issues.. Check out the Changelog at the bottom of this post for a rundown of all the big changes in detail.
Here's a quick outline of what's included:
A full set of character creation options, including 20 Home Worlds (this setting's Archetypes) 11 classes and a revised skill list to better suit the setting. As well, guidelines are provided on how to appropriately create a higher level party, with details on what sort of resources and finances they should have access to. A whole host of new talents across all five tiers, clocking in at 167 talents total. Some of these are entirely new designs, while some are copied over from various FFG books and modified appropriately.  Elite Advances, a new system to allow for playing as Astropaths, Untouchables and several other galactic oddities.  A complete equipment section, including rules for weapons, explosives, attachments, armour, custom ammunition types, cybernetics, servitors and general equipment.  As well, rules are provided for purchasing and acquiring services such as accommodation, void transport and healing.  Rules for Influence and Subtlety, allowing your Acolytes to climb the ranks of the Inquisition and receive concrete rewards for it, while feeling mechanical effects (good and bad) for how subtly they conduct their investigations. A system of Interludes to represent how your characters spend their time between sessions, letting them focus on self improvement, earning extra income, and various other pursuits.  Rules for psychic power usage, based upon the magic rules presented in the Genesys Core Rulebook and modified to suit the setting. Includes a handful of new abilities (heavily inspired by Cyvaris' work), as well as a Perils of the Warp table for each psychic discipline, a design idea taken from the failed beta of Dark Heresy 2e. Corruption and mutation rules, allowing characters to slowly succumb to the influence of Chaos over the course of a campaign. These took heavy design cues from Warhammer Fantasy Roleplay 3e, with some heavy modification. Expanded rules for fear and mental trauma, based upon the rules for the horror tone presented in the Genesys Core Rulebook. Includes an advantage/threat table for fear check results, and a large list of potential mental trauma effects to inspire GMs and players. A fully fleshed out NPC section, including a list of 17 NPC traits which can be used to create or modify your own adversaries, along with 65 fully statted adversaries. This doesn't cover the whole range of adversaries Acolytes might run into in a typical campaign, but provides a solid jumping-off point for GMs to fill the gaps.  I have lots of plans for future updates, which will roll out as I produce them. Keep an eye on this thread for development updates! 
It should be noted that the content in this PDF really isn't enough to allow a total newbie to understand the Warhammer 40,000 setting. I highly encourage anyone curious to get their hands on a copy of one of the Dark Heresy rulebooks (first or second edition works fine, they're both excellent for fluff) and give it a read; they'll give you the proper context to appreciate the material here. Also, the Genesys Core Rulebook is required, if that wasn't obvious. 
Please either post here or PM me if you spot anything which needs fixing or tweaking, and if you end up running a campaign with this, I'd love to hear about how it all goes, actual play experiences can be great feedback for design purposes. Plus it's just nice to hear what people have been doing with stuff I've made. I've also made a Google Drive folder with comment-enabled versions of each chapter of this conversion - feel free to put your feedback and corrections right onto the documents. 
Oh, and I highly recommend actually downloading the PDF; it's fully bookmarked and hyperlinked, something you miss out on if you view it in Google Drive. Makes navigation 10x easier.
 

- Book Link -
- Supplement currently at release 1.0 -
One of the only real absences from the core book is vehicle rules; that's now corrected. This book covers land and air vehicles, including a range of civillian, industrial and military vehicles. Importantly it doesn't cover voidships; they'll be the topic of a future expansion if I decide to cover them at all, they need a fair bit of attention.
It includes:
20 different land vehicles, from civilian autocarriages to Baneblade battle tanks.  12 different air vehicles, from cargo shuttles to military bombers. Options to customise the loadout and design of many of these vehicles to suit different roles.  A system of traits which can be universally applied to vehicles, to make the rules easier to parse and provide useful guidelines for homebrewing new vehicles. A range of weapons and other wargear for vehicles.  

- Book Link -
- Supplement currently at release 1.0.5, see bottom of post for changelogs -
My own take on a "monster manual" of sorts, this little expansion goes into detail on Tau armaments and NPC stat blocks. Eventually I plan to do one of these for a wide range of different opponents. Note that this is a first edition book; there might be some slight discrepancies in game balance between this and the new third edition of the core book, and the layout isn't consistent, but it should be totally usable still.
It includes:
Statistics for Tau weapons, armour and gear, and rules for using and modifying these as a human. Rules for Tau battlesuits, complete with a full host of support and weapons systems, and a custom crit table. Stats for a big variety of Tau enemies, including all the warriors of the Fire Caste, drones, the alien auxiliaries, and the civilian castes.  - Changelogs- 
Dark Heresy Core Book - Third Edition
 

Hey everyone, here's the work I've done on the Chambers Militant Armoury chapter so far. 
https://drive.google.com/file/d/1Yoq2zch0FxeouRIoeSDWovRkwYZPMioL/view?usp=sharing
What's done:
Rules for acquiring gear as Chambers Militant characters (they don't use typical Thrones or Influence). All ranged weapons for Sororitas, Grey Knights and Deathwatch. All melee weapons for Sororitas, Grey Knights and Deathwatch. All armour and forcefields for Sororitas, Grey Knights and Deathwatch. Armour attachments (I may add a few more of these so the formatting isn't finalised) What's not done:
Ammunition rules, including custom ammo. Grenades and explosives. Weapon attachments. General wargear. Familiars and servitors. Cybernetics. Let me know if anything seems missing or incorrect!
Update: It's all done! Whole armoury chapter should be ready to go, let me know if you notice any glaring omissions. 

Hey everyone, here's the work I've done on the Chambers Militant Armoury chapter so far. 
https://drive.google.com/file/d/1Yoq2zch0FxeouRIoeSDWovRkwYZPMioL/view?usp=sharing
What's done:
Rules for acquiring gear as Chambers Militant characters (they don't use typical Thrones or Influence). All ranged weapons for Sororitas, Grey Knights and Deathwatch. All melee weapons for Sororitas, Grey Knights and Deathwatch. All armour and forcefields for Sororitas, Grey Knights and Deathwatch. Armour attachments (I may add a few more of these so the formatting isn't finalised) What's not done:
Ammunition rules, including custom ammo. Grenades and explosives. Weapon attachments. General wargear. Familiars and servitors. Cybernetics. Let me know if anything seems missing or incorrect!
Update: It's all done! Whole armoury chapter should be ready to go, let me know if you notice any glaring omissions. 

Hey everyone, here's the work I've done on the Chambers Militant Armoury chapter so far. 
https://drive.google.com/file/d/1Yoq2zch0FxeouRIoeSDWovRkwYZPMioL/view?usp=sharing
What's done:
Rules for acquiring gear as Chambers Militant characters (they don't use typical Thrones or Influence). All ranged weapons for Sororitas, Grey Knights and Deathwatch. All melee weapons for Sororitas, Grey Knights and Deathwatch. All armour and forcefields for Sororitas, Grey Knights and Deathwatch. Armour attachments (I may add a few more of these so the formatting isn't finalised) What's not done:
Ammunition rules, including custom ammo. Grenades and explosives. Weapon attachments. General wargear. Familiars and servitors. Cybernetics. Let me know if anything seems missing or incorrect!
Update: It's all done! Whole armoury chapter should be ready to go, let me know if you notice any glaring omissions. 

We have some great stuff on the horizon! This post sums it up nicely, if you are wanting a beefy post!
https://www.patreon.com/posts/37155192

Here's an example of how the career writeups are looking now. 

Totally flawless, nothing to see here.

Back at it again.

Starting to build out Deathwatch character creation. I've tweaked the Elite Advance to simplify it a bit, and I've added flaws to every chapter (not too happy with where Ultramarines are at, they're a tough one to assign a good gameplay flaw to). 
Decided to include Primaris Marines as well. 

https://www.youtube.com/watch?v=siwpn14IE7E
 

Totally flawless, nothing to see here.

Imperial Armour 1.0 is ready to go! Brace yourself for rampant typos and balance issues, this is very fresh 😛 
I'll be putting out a small errata update to the Core Book over the next few days as well, which will apply some tweaks to personal scale weapons and how they interact with vehicles.
https://drive.google.com/file/d/1mC5Wa71fxJjbUKDKiEcp9RYorN2cwKAO/view?usp=sharing

Totally flawless, nothing to see here.

I want to think Space Wolves are flawless!

This is putting other, official books to shame! 😮

Back at it again.

Starting to build out Deathwatch character creation. I've tweaked the Elite Advance to simplify it a bit, and I've added flaws to every chapter (not too happy with where Ultramarines are at, they're a tough one to assign a good gameplay flaw to). 
Decided to include Primaris Marines as well. 

Starting to build out Deathwatch character creation. I've tweaked the Elite Advance to simplify it a bit, and I've added flaws to every chapter (not too happy with where Ultramarines are at, they're a tough one to assign a good gameplay flaw to). 
Decided to include Primaris Marines as well. 

Imperial Armour 1.0 is ready to go! Brace yourself for rampant typos and balance issues, this is very fresh 😛 
I'll be putting out a small errata update to the Core Book over the next few days as well, which will apply some tweaks to personal scale weapons and how they interact with vehicles.
https://drive.google.com/file/d/1mC5Wa71fxJjbUKDKiEcp9RYorN2cwKAO/view?usp=sharing

Starting to build out Deathwatch character creation. I've tweaked the Elite Advance to simplify it a bit, and I've added flaws to every chapter (not too happy with where Ultramarines are at, they're a tough one to assign a good gameplay flaw to). 
Decided to include Primaris Marines as well. 

Back at it again.

https://www.youtube.com/watch?v=siwpn14IE7E
 

Back at it again.