Great game; would recommend if you continue with it to look into more complex level designs and fixed size waves as a form of progression to enhance replayability. Controls are super smooth, and very fun; no glitchiness at all despite the fact that you're dealing with complex physics; really well done.
thanks, I definitely agree that it needs real progression. 1 infinite wave was the easiest thing to get up and running while I focused on the more important gameplay and feel. I'm thinking structured waves with some more enemy and projectile variety will help a lot