She was actually costumed to loosely fit in with her even more revealing and risqué outfit from the New 52 comics. The Joker's aesthetic had nothing to do with it. Margot also chose her own influence on the final design, which was inspiration taken from Debbie Harry. I thought her speech and mannerisms were relatively spot on to her character from Batman: The Animated Series. So I fully appreciated how she approached the role. She just recently confirmed a solo movie for Harley, and she hopes to bring back the traditional jester outfit. So hopefully that works out.