This is just my opinion, but I don't think Catwoman would be that great of a film no matter what they tried. I just don't think the character/story translate well to live-action without it being cheesy and campy, especially without a larger character to sustain the movie. Same goes with Wonder Woman and Aquaman and whathaveyou.
One character/story I think could work though is something on Bishop from the X-Men universe.