I also think Wonder Woman looks terrible, and part of that is because I think the actress doesn't look good (for the role I mean). Her facial features are soft and she doesn't look aged enough. Granted, it's a picture which means mostly nothing when it comes to how it will look in the movie and it can all be rectified with a good performance. She could put on a good enough performance that everything flies out of the window. And as mentioned, it is just a picture without any real worth to it outside of the movie itself. It probably looks worse since both Batman/Superman are looking amazing.
I've always thought the female lead from John Carter had the right kind of look. She didn't look young in the movie, but not old either. And she had the kind of face which can look a bit tougher rather than model like. It would've been good if they had casted someone with tougher facial features. Basically, someone who doesn't look like a girl in her twenties playing pretend warrior.