Its pretty clean, I didn't play for that long, but also didn't encounter any Bugs or anything. Soundeffects are simple but fitting, music is missing, apart from the Titlescreen, I'd say either have music in title and level or not on any one of the two.
Its got a nice difficulty curve, with more and faster enemies, but the super long scoreboard kind of feels overkill, I can see People getting a lot higher scores then I did (136) but not 3 or 4 digits more. Maybe just get rid of leading 0's?
Also doesn't really strike me as a PC or Controller Game, more like some short Phone Game, altho I don't really know how you'd do the 2 shooting colors apart from onscreen buttons.