Some other ideas:
Warrior:Give it the "cloaked when idle" ability, this would be useful for ambushing enemy raiders, and it fits the factory's theme.
Leveler:I haven't seen anyone use it to smooth terrains, maybe it should have a area smooth effect when it dead instead, that would be more easy to use.
As for the mobile anti-airs:
Devestator(the light veh AA):Give it a 120°maximum fire angle, but it should have the longest range.
Vandal: Simply make it more spammy, I don't see any reason why a anti-air unit shouldn't be spammy.
Archangel: Give it some very limited anti-land capability.
Copperhead: Give it some buring effect, flames in the sky would be dangerous for gunships.
Tarantula: Make it into the fastest mobile AA, this would fits a all terrain unit well.
Flail:Give it a damage effect that can decrease enemy air unit's flying altitude, so they are more vulnerable to scalpel, mace etc.