I liked it! Quite addictive! Only thing I would add is that having to wait for enemies to show up at the start is a little frustrating.
Thanks for letting me know you like it. And yes, even I in development was caught by the addictive nature ^^
How it now works is: first we wait to spawn an enemy until the player moves, then we spawn an enemy and we wait until the first enemy is killed until we start spawning.
I added this wait because otherwise the player would be dropped in the game instantly from the start-screen ... and I figured people maybe had to get adjusted to the movement before enemies spawned.
But I see your point ... I probably should make it that the first time you have to wait, but after a restart it's just instant mayhem and chaos ^^