Which part should I audition for in Grease?

I have the voice for Sandy, but if I'm being perfectly honest, she bores me. Her character is incredibly two dimensional and while it's a great singing role, it's not a very good acting role. However, while I do love to act, my acting is much weaker than my singing. I feel like I'd have a better chance at landing at least the understudy than if I tried out for Rizzo, but it's really not much fun being a goody two shoes. On top of that, I'm a freshman, and so I don't really have much of a chance to get a lead anyway. It would be a lot of fun to play one of the Pink Ladies, but I would rather have a larger part, or at least the opportunity to have one, even if my chances of landing it aren't so great. Who should I audition for?