I would think they would let your 6 year old ride alone on Peter Pan. Snow White, Alice in Wonderland and Mr Toads all have four person cars, so you can ride those together. Peter Pan is always one of the worst lines in the park. And, unlike DW, there is no FP, so get there early in the day. Not sure about Dumbo, I never ride it. There’s just something about a flying elephant that makes me nervous…lol.