Well, crap. I can't answer with the one I'd like to because it would be giving too much about something away. Incredibly vague, I know. Maybe if I remember later I'll be able to come back the answer I really wanted to leave. (+100 points to you if you understand who I mean.)
Other than that can I be....
Okay, sort of cheesy, I know, and this movie was so, so terribly bad, but I had all of the books and loved the TV show when I was little. And wiki tells me she's on the list of superheroines, so she counts. Riding a white horse (Starlite!) with a rainbow colored mane who gets to create rainbow roads accompanied by a ridiculously cute entourage? I mean, really, look at Sprite - bloody adorable. She's the spectra queen, basically. I'm all over this. (And if I had it my way, I'd totally have a mash-up with Care Bears.)