I like Marry Me A Little at the end of Act I very much. To me it's the perfect step in Bobby's solos throughout the show that build to Being Alive. I've always looked at is as:
Someone is Waiting: I'll get married when I find a perfect person
Marry Me A Little: Well... she doesn't have to be perfect, but I'll hold something back and won't fully open myself up for hurt.
Being Alive: Maybe it won't be perfect, and that's ok?