Thank you everybody for your help! :D I feel like I have become so much more informed about hair history now. Here I decided to go with an Eton crop a la Joséphine Baker because I feel that Tiana would have pulled it of magnificently! ;D
MINI RANT: How come Tiana is the ONLY Disney princess (Elsa is a queen) to never have her hair down?! And no “that was how black women wore their hair back then” (I have seen this argument too many times to count) because 1. The movie is not 100% historically accurate (Maldonia?! Talking bugs and animals?! Magic!!?!) and 2. When she married Naveen as a frog and was transformed back to herself, she got a magnificent dress and accessories from Glob knows here (The Ministry of Magic?) and that magic could easily have gotten rid of her hair-ties/pins in order to show off her curls, but nooooo. *sigh* At least we have gorgeous fanart by Loryn Brantzto look at.
EDIT: And now I was reminded of the concept art where her hair IS down and big and stunning, and now I am even more upset… (-_-)