The 'auto-fire' has got to go! Could you go with the spacebar or 'z-x-c' thing? Or up arrow if you do a WASD config for lefties/ambs? Nice simple concept and all, but everything feels like it's moving in slow motion. I'm not saying make it a super fast game, but speed up the protagonist ship and the enemies. maybe just 33 to 50% more.
Like the pix animation. Not a bad job there.
This just needs to be fleshed out a bit more to be a real game. I'm guessing you have at least another 10 or so levels you'd like to add to this and then for it to have a real ending?
Good concepts all around but it's...lacking.