Re: How Long Was Bruce Wayne Actually Batman in this Trilogy?
I would have loved TDKR starting with a montage sequence showing us all the rouges he has been fighting while being hunted, catching us up to the 8 year point where he is now busted up and no longer needed. Then he retires. Bruce has has continued being Batman, "lost in his monster" and develops his death wish. It would also explain his over-confidence when Bane finally shows up because in a way he's been waiting for someone who could beat him.
Just brainstorming but it might have been interesting if Bane takes over and unleashes all the criminals we glimpsed in flashbacks and have fleshed out more. I really think the only reason Bane doesn't involve Arkham is because it would make Joker's absence very obvious.