I am new in here, but I come from a gaming community where everyone gives their honest opinions. So here I go:
The new power-ups were quite interesting, but a bit too over powered for my tastes. I like levels with a bit of challenge. The new environments are creative, but they don't look as good as the original ones. Although, the level editor doesn't give us the chance to create high quality graphics that built-in environments use, so I'll have to forgive you on that one. I admire the effort you put in them, though. (oh the irony?
I can see that you've put your effort mostly in making those powerups and environments, but you should have put as much effort in making those levels (at least the ones between the levels demonstrating the power-ups)! Levels are as important as the new content! I gave you a B+ overall.
I am sorry if I am too harsh, but like I said, I come from a different place where people are not as nice as people in here are. In my opinion, criticism/real feedback/honesty comes before kindness.
If you plan on making more level sets with new power-ups, I suggest you put a good amount of effort in making those levels too.