The TWE being focused with advancements and technological powers while not using laser guns and shit, should still be using something that isn’t a non pulse rifle and weapons unable to take on a single UPP on their own.
I believe a system like the Stoner 63, and being able to deeply modify your rifle (to give those custom heads the scratch they need) with barrels, stocks, magazines with attachments to boot would give the TWE a more tactical and unique feel to them. Balance and gameplay wise as a ERT they’ll be forced to have their guns be RNG made. though with some coding and generalization they can be made to have some basis with the weapon system their given.
In short, A in depth weapon system like the Stoner 63 would not only make the TWE stand out with their weapons but flex their technology to the UPP and other foes they will run against.