Moana seems to be a great improvement from most Disney princesses.
Usually it's all about what they want and what makes them happy.
Moana does want things too. She does also have dreams. She longs for adventure out in the ocean. But she also understands her responsibility to her people. She finds a way to save them and her home and she does that by going on this journey.
Point I'm trying to make is she's not motivated by her own selfish pursuits or interests. Unlike a certain mermaid who will remain nameless.