Actually, I'll be a voice of dissention here. I think the Hulk is True Neutral. He doesn't actually want anything other than to be left alone. This is about at Neutral as it gets. The only time he goes on rampages is when he's being chased/hounded. He doesn't go out of his way to break rules, or disrepect authority. He is pretty much completely oblivious to authority.
Hulk is neutral in my books.
I'm not a DC reader, so my exposure to Catwoman is from the cartoons and one of the Batman movies. Yeah, I'd buy CN for her. Her whole goal is a Tyler Durdenesque rejection of male domination and the status quo. Her actions are whimsical and she's pretty much completely unreliable. Sure, I'll go with that one.
Black Cat? Been a long time since I read Spider Man. Not sure if she's extreme enough for chaotic. Neutral I buy. Borderline case IMO.