I'm sure this has been suggested a lot, but why not add more upgrades? After 200, there aren't anymore upgrades on the characters, and I just think it'd be cool if there were more available perks for upgrading them further. And maybe at level 1000, you reset them and they gain a huge increase in power? And then more upgrades. Just seems like good idea to me.
Could you change the controls? I don't like the fact that my character moves wherever my mouse goes. Change it to the arrow keys/WASD keys. And space to jump.
We changed the profile hosting the game in order to prepare it for the new html5 version coming next week (hopefully early in the week).