When the enemy is running in and out of cover, I don't use the "fire until dead" option since then it's more likely they will stop their action. If you choose one shot at the time they will have a better chance of staying with the target.
The idea about limiting the uses of the repair kit is a good one, and I've thought about it. I have some problems figuring out how to tell the player how many times he has left or how many times he has used it tho. Don't think there's a good solution for that since it's hard to keep track of one repair kit. If one is used a couple of times, and then the player gets a new one, that will have the same amount of uses left. I'll spend some more time thinking of a solution, promise. And doesn't the base mechanic repair the weapons for free? There are also a few traders that do it for a small fee, so preventing the player from switching to new weapons will only work until that's discovered