Really cool & polished game.
the visuals a really neat & the controls very tight.
In terms of feedback I mostly agree with what Jrevel pointed out.
I'll just add this point :
some robots dies in 2 hits and some in 4 but there's no way to tell them apart. this can be a bit frustrating & confusing. simple sprite or color change would really help in term of readability so you know what you're up against.
All in all it's a really solid entry. And with some minor adjustements it would really hit the spot perfectly.
Great job :)