The allies idea seems like a bad idea to me because it forces the player to replay the levels that were frustrating for them to get more allies, adding unnecessary replay value.
medics are only useful if there is more than one since you can gather all of them and the injured soldiers under a cam net or two, with a sniper and spec ops outside to defend.
Yeah, it's great game :) I play it from time to time and developing a TBS of my own, too