Wow, I really like the game! Music is cool and concept is cool. I don't like hardcore games but really liked this one even if the difficulty is a little to high for me.
I assume that the enemies' movement are hardscripted so with several tries the player will remember all the patterns and can complete the level. Make the enemies' behavior procedural or dependant on smth (like in pac-man) will increase the difficulty of the game and replayability.
Good job!