Cobalt Jade, I quite like costume 2, very appropriate.

I definitely imagine something that has both flowy and structured elements. The bodice in the Baynes illustrations looks quite structured and solid while the skirt and scarf flow. The crown is massive and heavy, but her hair is wild, the perfect blend of strength and movement. 

Lu Valiant, MINOAN is exactly what I was trying to think of! (careful googling it everyone, it’s revealing, don’t want that part) It has the right colors and structure. I also like something a bit ancient Babylonian (others have said Persian).

The other thing to consider is layers that can shift and alter throughout the movie so that it doesn’t get boring. A robe/cape to wear over everything at first, more sashes and drapes and jewels after “shopping” with uncle Andrew, etc.