I'm completely honest when I say this is probably my most favorite game I've played on Newgrounds in the 9+ years I've been active. Great job! Simply fun, cute graphics, great mechanics.
The only thing I will say is you might want to lower the probability of some of the items. By level 2, I was a double high jumpin', wall climbin', block breakin', cool-as-a-cucumber, daft punk-esque orb seekin' machine. It only took me till level 4 to snag some missiles and up my attack power to around 5 or so.
I know I'm missed listing a powerup or two, but I was bested by some acid on level 6. :( Insta-death is alright, but you might want to add the functionality to look down so the player knows they aren't about to jump straight into a vat o' bad.
But all in all, wonderful game you've made. :D 10/10. Would play again.