I thought it was a near perfect balance. They took it to the edge but didn't go so far that it became alienating. Also, I thought it really played into the story. It wasn't just having a dark character for the sake of being dark or because they needed some character beats.

As for Butch and Sundance, it's almost impossible to judge. By the time I saw it, so much of the stuff that made it famous had been copied and/or parodied. Some classic scenes but I don't feel like it aged as well as a lot of other films from that era.