Leather jacket looks the coolest, if wear those pants and gauntlets. I'm worried about the movies and comics, no one seems to be able to write for her. She should be calm, intelligent, beautiful, feminine and not just a sex symbol. In injustice she's to aggressive. I think the best depiction is in crisis on two earths. just make her cool. Guys can be pigs.
While I'm not a girl I would say leather. It's the most functional as it's more winterized and winter is coming around the corner. She doesn't need the armor as she has that bullet proof indestructibility that superman has.