But the Joker had some interesting aspects to begin with that Nolan could use to touch on the original character, while expanding him.
For example, as you point out, the Joker was once a prankster who robbed banks. Indeed, that is the way the general public, raised on old comics, the 1960s series and even the Burton film, think of him. The opening sequence of the movie took that persona and brought it into the "Nolanverse." There was something there for Nolan to work with.
It seems to me that there's nothing like that for Nolan to use with Bane. THerefore, the only way for Nolan to make Bane "work" would be to make him a completely different character than the one in comics. At which point, why bother using him, especially given the fact that no one outside of a small group of fans knows, or cares, about him?
