okay, this is just a vague idea at the moment, but it's been creeping up on me several times, so perhaps it's worth thinking through, and perhaps somebody would like to chime in.
what if the plasma used for weapons was decaying over time?
I'm not talking about "on the battlefield", since that's mere minutes (...in fact, 0 minutes...) of global time. but perhaps within hours after "charging" the plasma clips? the fluff text explanation would be that the plasma clips are in effect miniature plasma containment cells, and are filled with a ready-to-use high-energy plasma before the battle. the charging of the clip takes a few minutes, so it can't be done on-the-fly. once the plasma is in the containment, it can either be used or it decays within hours.
- plasma clips are effectively non-recoverable. you can pick them up on the battlefield, you can use them in the battle, but you can't bring 'em home. until you learn to manufacture them, you can only use what you scavenge in the current battle.
- elerium becomes more important. especially in late-game situations where you have lots of plasma weapons, you need to think twice about actually using them, and should avoid relying on them entirely.
- the tactical battle might become more interesting, because now it actually makes sense to pick up the weapons of dead aliens (or at least their plasma clips)
- you could still manufacture clips, but if you bring them into a battle, you lose them, whether you used them or not. (this might cause problems for base defense missions... not sure how to resolve that)
- the same principle should, of course, apply to the craft weapon. it should be reduced to something like 10 shots, and use elerium for re-charging. since there's no such thing as a "non-recoverable" switch for craft ammo, we could simply claim that due to the larger containment cell in the craft weapon, the plasma decay rate is greatly reduced (years instead of hours).
comments? criticism? sounds fun or boring?