I really meant that they are the ultimate clean slate. With all the myriad Skills and Talents, coupled with Chapter Traits, one can craft and built a Career Path to becoming whatever one wishes their Marine to ultimately become. A Close Quarters Enthusiast or Ranged Marksman, a Lore, Tech or Medic Assistant/Backup or Driver/Pilot or whatever. They have the fewest restrictions compared to the other "Specialist" Classes.
That's my plan. I'm making a tactical marine that's focusing on driving atm (ravenwing veteran), so I've invested everything I had into being a good driver (maxed out agility) and shooter (maxed out BS, Bolter Mastery). I was just thinking about what role to fill when I'm not driving/shooting from a bike, and I was a bit worried that I'd be slightly behind every other party member (ranged focused techmarine, devastator, assault marine and apothecary).
With its flexibility and general lack of restrictions (having access to most Talents and Skills that Devs and Assault do) I've always thought about the Tactical similarly.
That sounds overly optimistic. Tacticals get most useful shooting Talents and barely anything for melee (and what they do get for melee is ridiculously late in the ranks). They are no less restricted than any other Specialty in the game, and trying to build them into anything other than a straight-up shooter with some command stuff on the side will require relying heavily on Chapter advances, advanced Specialties, Deeds and Honors.
And I know Rites of Battle was from a while ago, but I thought the Ultra Mk.IX rifle was pretty much the top of the line for sniper rifles in Deathwatch. Even though it doesn't get bonuses for being a Bolter.
Not by a long shot. (Pun not intended).
Going by errata stats:
Stalker Bolter: Range 200m Damage d10+9 Pen 4 Clip 24 Reload Full Qualities: Accurate, Tearing
Ultra Rifle: Range 250m Damage d10+4 Pen 2 Clip 5 Reload Full Qualities: Accurate, Felling (1), Toxic
Slightly better range, abysmal ammo capacity, worse Penetration. Felling will about make up for the damage difference, but only against enemies that have Unnatural Toughness (admittedly, quite a lot in DW, but it will still rarely come out on top damage-wise). Toxic is rather weak considering it doesn't affect Tyranids and Daemons at all and it's almost impossible for enemy Astartes to fail the roll.
That's all before you even consider all the awesome kinds of ammo you can put in Stalker:
Stalker - absolutely silent with no drawbacks
Kraken - up that range to 300m, blowing Ultra out of the water, and increase the Pen to 8 (what power armor again?)
Hellfire - ignore Natural Armor altogether (Tyranids can suck it!) and inflict Righteous Fury on 9 and 10
Vengeance - Pen 9 and Felling (1), need I say more?
Witch Bolts - mess up psykers and daemons something fierce.
Combine it with Bolter Mastery and that free clip of special ammo Tacmarines get for free each mission, and it's not even a competition, Stalker Bolter is clearly the superior sniping implement for Tacticals (and for anyone else, for that matter).