yea. they could re-create characters. just because one guy made the character one way for a cartoon show for kids, doesn't mean someone else couldn't change her for a different audience. Also, along with ras al ghul, joker and two face's backstories were completely changed. Joker has none, and wears makeup, instead of being Jack Napier who fell into a vat of acid and went crazy, trying to pull pranks on batman. Two-face was originally splashed with acid to his face, and sewed two suits together, so his character was also changed. Depending on who the writer/director is, characters are very flexible.
crisping glover would be a great joker for or not for nolan's world...he's just a bit
too out there.