The graphics look nice. Definitely better than the average App Store crap imho. The particle effects are a bit too much for my taste though. While I found the graphics polished, I can't find anything in the video or app description that would make me want to play this game right now. Something that would let me think: "F* it, what's 99 cents?". That may be a well thought of combo mechanism, dual ship power-ups, size modifiers etc. And if they're already there, show them!

I think the strength of games like this lies in competing with yourself and others. For example I thought Flappy Bird was a terrible game, but I HAD to beat my brothers highscore. So that would be another way to generate downloads. In fact I think another strength of Flappy Bird is that you don't have a warming up phase regarding the difficulty which keeps you in the flow. Players in the flow keep gaming on and on and therefore expose your game to others.

I hope my thoughts can help you to improve your game. Regards, a fellow indie who has yet to launch his game.