Great game and it could have been even better if it was a little less dry, the problem is that there is not much visual and auditory feedback, for example the interaction with the enemies are not very striking, when you kill an enemy there is no visual feedback, screen shake, animation, etc.... . Adding some would make the elimination of the enemies much more rewarding. I advise you to go and see the conference "Juice it or lose it" which could help you to improve the feeling of the game.
But anyway good job :)
I'd appreciate it if you want to try my game too, I'm with some rates :D
Thanks!