Re: Uncanny Plot Similarities between The Dark Knight Rises & Batman Begins (SPOILERS
Talia was there to fulfill Ra's work. She said as much in her reveal. Revenge on Bruce was secondary. Bane, on the other hand, was intent on proving himself to be the better man than Bruce or Ra's. He'd break the man who threw away a position in the League that Bane was due and accomplish what his savior failed to accomplish.
With submission, in respect to Dagget, he would be in the same boat as the last of Gotham's mob in TDK. That seems plausible; given how the Dent Act took out traditional crime, white collar seems the next big thing.
The Nuke, again, presented the opportunity for a plausible No Man's Land scenario. It was intrinsic to Bane being able to dangle hope before Gotham; the citizens had no idea that the bomb was going to go off no matter what. Bane didn't force the people to go berserk. Again, he essentially said "here you go", not "do this or you're dead."
The film didn't have the time necessary to draw out five months worth of executions; that would be verging on unnecessary filler. The tour of Crane's court and the executions simply allowed Nolan to show us how bad things were in Gotham, rather than take the easy way of having someone say "by the way, they're killing people in the kangaroo court."
The circumstances of Batman's leadership elevate it beyond the timeframe for his leadership. By circumstances, I intend to say that he stepped from being the shadowed beast/murderer to being a leader and a symbol of justice. It was integral to Bruce's character development.
"I am for no master nor moral persuasion. I am for myself. What your yearning soul, madam, might mistake for loyalty to person or Purpose is merely a firm and, aye, principled determination to accept responsibility only for myself and my own actions." - Elric of Melnibone, The Revenge of the Rose (Elric: Swords and Roses).