There are several characters that need dramatic costumes in the film. here are a few.

Captain Cogsworth
This is the most know pirate in all of the skies, his crew steals everything and gives him the best of it. he dresses very expensive, but gets dirty himself. So he would need to be able to swash buckle and swing from ship to ship.

Emma
she is the love interest of Gideon, she would need to have something to obscure her face like a half mask or something so she is not recognizable at first.

The Architect
The architect would be very simple but a very worn styalized lab coat. he is a very thin and frail man that doesn't talk much, his clothes would need to show what a dignified character he is. (there doesn't have to be a lab coat just a suggestion.)

also there are plenty of extras to design for.