Enjoyed this a lot. It's exactly the sort of game that I'm terrible at, but will keep trying anyway. Didn't manage to beat even stage 1, but I had fun.
One suggestion, that I probably ought to make to everyone but am mostly bothering because I don't plan to delete this one, is that it'd be really nice to have an exit button. The game defaults to fullscreen, so I have to use alt-f4 to leave.