respectfully, i hate this argument but yes all KU get westars. Stat wise the DC-15x and westar do the same damage in the same amount of time. The z-6 on the other hand is great on paper but in game its god awful. the sniper if anything at all gives the class and sub unit as a whole a ranged option and overall can bring more roleplay options to the table like long range scouting and such.
21st has a completely full Support branch (10 troopers in total) and talking with gadget the first time the conversation of changing KU WS he didnt want more support troopers. HVO definitely was talked about but battalion balancing and community feedback were the only roadblocks to making that suggestion instead.
I personally chose ARF solely on the long range recon factor. A JT can do the job sure but they still have to get up closer than a ARF trooper would with their sniper. I want KU to move as one full unit when away from the main battalion and not individuals. Having the Jetpack, Medkit and Sniper combo is devastating when used properly, especially in the well trained group that Kellers Unit strives to be (2ndAC wit a perma weapon at this point).
Also our Aerial trooper has doubled as a Pilot seeing as the "support" is a medic