I had a thought for humans to have a med pack. Now I know what you're saying, "But Terror, med packs ruined gloom!" well my idea for a med pack is a bit different. Instead of everyone carrying around a usable medicine unit, which only heals the wearer for a certain amount of health, my idea of a med pack would replace a Battery/Jet Pack and would only be used to heal others or healing thyself (smirk) while healing others. This would promote humans sticking together, which is where humans excel, and also add a new "class" of human.
The medpack would also replace or augment those lame poison curing stimpacks, because no one really buys or uses them. Other balance issues can surely be adressed if a med pack is put into play i.e. make it really expensive, limited in use, or available in stage 3 only so as not disturb the lower stage balance but help with those rampaging Tyrants

I'm sure the game developers (Timbo) could work it in effectively somehow without offsetting things too much.