Lungfishopolis is the best level ever, especially with the ridiculous lungfish freedom fighters, complete with headbands and tiny definitely-not-AK-47s.
Not to mention that even the so-called instructors in the game all seem to admit that having kickass psychic powers isn't about using them responsibly so much as just doing awesome stuff for the hell of it.
Sasha Nein: "You will learn to control these emotions, focus them, concentrate then, and release them."
Razputin: "As therapy?"
Sasha Nein: "No, as firepower."
Ford Cruller: "Now you have to promise only to use your power of Pyrokinesis when it's really, really important or really, really entertaining."
Ford Cruller: "And if you're doing it to impress girls, make sure none of them are wearing a lot of hairspray."