Glitch on the boss!
...on the evil-Tails-robot boss, I encountered a glitch in which the boss fired energy balls in completely random directions, usually directly underneath him (despite my being on the other side of the square). This glitch occurred after I died on the boss and started at the last checkpoint a few times.
Aside from that glitch, the one you mentioned in your comments, and a rather steep difficulty curve, this has pretty good potential. Just toss some enemies and maybe a storyline in there and make some fixes, and it should be good.