Also I'd little add: I think it does not make quite a difference havin the sniper rifle and a marksman rifle: an original idea may be to replace that marksman thing with an "improved assault rifle" researchable till start. It could be a slightly improved version of the vanilla AR rifle designed from scratch. Or maybe replaced with some other human weapons. My 2 cent's.
Also, since a submachine gun (SMG) is already present, i'd revert the machine pistol to vanilla pistol, but grant it auto shot capabilities, and a fair weakness compared to the magnum .44. And lasrly decrease clip size from 24 to 15.
The DMR fills a different role than the heavier sniper rifle, Just like the machine pistol fills a different role than the submachine gun. All of these weapons have roles to play.
Machine pistol has a ridiculous cyclic rate and therefore is wildly inaccurate in auto modes, but up close and in the early game, it can drop a ton of hits at close range.
The SMG is slightly weaker than the machine pistol (design choice here) but is incredibly accurate at midrange and costs less TUs for an auto shot than the assault rifle.
The shotgun puts hits all over the place and is rather weak against armor, but can kill multiple targets in one shot and is excellent for close quarters work.
The Assault rifle is the backbone of your squad, good all around.
The Designated Marksman's Rifle allows a squad to have someone mobile but still capable of precision shooting.
The LMG is slightly weaker than the assault rifle (again, design choice) but has an absurd rate of fire and (should) be relatively accurate in burst modes further out than other weapons.
The sniper rifle is heavy and can only be fired accurately when stationary, but does a significant amount of damage and can aim shot across the map if you have spotters.
At least, that's my take on what I am putting together.
