As I said before, I think Naveen is even better developed, however Tiana herself is a multi-layered character with a diverse range of personality traits, some of which do get challenged throughout her adventure and she not only develops herself, but causes other characters to develop too.

I am just really impressed with how all the characters in this movie interact and help each other develop during the story. I guess that's partly why I've never been able to choose a favourite character - I just love them for how well they all go together! :D

^^