I am sorry if that appears a bit off-topic or harsh. I wasn't trying to smother a brilliant idea, I just wanted to point out that while it really is cool and I really like it, it appears that Chiko is putting a lot of energy into creating those weapon and ammo sprites - although they won't be able to be used. better to point that out sooner than later, I thought.
Like I said, if you make those designs generator-friendly, it will never be a problem. that is something worth thinking about for further designing, isn't it?
and to be more on-topic, I always thought that the Heavy Weapon line for Human soldiers should at least include some kind of bipod or tripod. come to think of it, you should be able to "set them up", greatly increasing accuracy at the cost of rendering your soldier immobile until he either spends time units folding it - or abandons the weapon. There's something that could also be upgraded once "alien alloys" are researched: weapons get lighter, so you have more energy left for actions.
I still think that the upgrades only stay manageable if you make them global. Once you research alien alloys, additional research topics open up, where perhaps you can opt to make weapons either stronger or lighter, but always affecting all your human weapons. Else this will turn into an RPG-style management for weapons, and I don't think that goes well with this game.