When her kingdom is sacked by the aztecs, a naive princess must use dangerous magic to protect the last of her people from the brutal jaguar warriors.

This logline works – it has all the major beats it needs and the story is clear enough.

I urge you to push yourself and find a different/better flaw for the princes – ‘naive’ is so overused and passe a flaw for female characters. It comes across as more of a convenience flaw for the sake of giving her one than a genuine flaw which relates to the story. If she was a selfish, arrogant or a stuck up A-holee, she would need to learn to care about other people. this way you can give her a real negative character flaw which would make her inner journey interesting.