I'm gonna start off with saying these: "It's good to see a character with a 360 degree attack radius whose arm/gun doesn't just simply rotate" the extra effort really makes a difference to me.
At Cyplode34: I was sort of annoyed when my weapon was overheating super-fast too, but I'm equipped with the means to inject coolant and freeze kits for a reason, it feels like you were expected to manage your powerups more than just hold your mouse button down and put your cursor over what you want dead for the entire game. Managing Rockets and Powerups for when huge waves show up give the game depth.
As far as my review of the game itself, most of the animarions were well done, and although the gameplay does have a lot to it, it's still fun to play.
One tip I might give you from one designer to another, if you're not going to have depth of story, you'll want to fill that gap with mayham or amazing visuals.
(As an example: shooting enemy rockets would cause them to spin out, crash and damage/destroy anything they land on, rather than just explodiings, aand so on. Or have the destroyed aircrafts crash into and damage the buildings behind the playfield.)
Great game though, keep up the good work.