I personally like the idea here, it is too cheap to build for what it is, however.
And for it to be truly effective, one has to have AAI installed to make it fire at enemies on it's own.
For a "in the middle of nowhere outpost that you go to for emergency supplies", it works on lower evolution levels (With AAI, otherwise it is completely defenseless out there).
If possible, I think adding support for Bob's Vehicle Equipment would make it upgradable for higher biter levels, being able to outfit it with shields and more weapons. (As of right now, the mod gives it a negligible size of grid).
Anyway, just minor things out there. Now the only thing we need is a vulture and then we'd be onto something.
