Its good, There are some things I would change. But they are just my own personal opinions.
Like I would use Nightwing instead of Jean Paul Valley. I would make Nightwing someone who is skilled in fighting and martial ats (a little) and maybe (using the Arkham Asylum idea, which I love) maybe one of the criminals who broke out kills Richard Grayson's parents. This would move Grayson into action.
I would have Grayson be acting totally on his own, a seperate entity from Batman all together. But since he isn't as skilled as Batman he isn't as unstoppable.
But he would get a little screen time. The most screen time would go to Batman as he battles on and we see him get physically and emotionally drained. This could be a few years into his career so he is still relativly new. He is on his way, however to be the unstoppable Batman we know and love.
Anyway
I think Bane, like in the comics, should be intoduced slowly. Although we would see him and his henchman setting all these things up. Have characters mutter his name in the beginning. Have Bruce and Alfred read about him in old papers and such. Then somewhere near the middle Bane attacks Killer Croc (who could be the human version we have read about here) and Batman finds Croc severaly beaten with both arms and legs broken several broken ribs, a broken jaw, broken nose, practically everything broken that you cane get and still live and move a little.
Along the way we as the audiance would slowly get reveals too, but would probably see Bane sooner than Batman would.
But his reputation and Batman's fear of him would get built up until the final confrontation at the end.
Eventually I would have Batman meet up with Grayson who used Batman's costume gimmick to help him scare criminals (because if he is somehow associated with Batman that gives him more of an advantage, gives him some credibility, than if he just put on a costume and went out on his own.) So Grayson acted as though he is partners with Batman.
Anyway, they meet up and despite Batman's complete unwillingness to allow Grayson to help him one little bit Batman is too physically and emotionally weak to stop Grayson.
Plus maybe he had just come from a fight with Poison Ivy or the Scarecrow, and he needs medical attention. When Alfred meets Grayson he could say something like Welcome to the team or something. (Alfred seems more accepting.)
The use of Grayson as Nightwing would only work in this film I think. Because Batman is SOOO overwhelmed that Grayson would be able to actually him him some.
Also in this film Gordon would almost be part of the team, part of Batman's army in this film. I would even have a scene where Gordon fights side by side with Batman.
Also i would show that the cops in this film aren't incappable of protecting the city. They just need Batman now more than ever.
As Batman fights some criminals we have seen before, and some new ones (this would be a good film to slip in some characters we haven't seen yet and may never see again: Killer Moth, Posion Ivy, Killer Croc, Black mask, so on.)
Batman also becomes more of a public figure too, while in previous films he was more of a myth and a vigilantee, and even someone people didn't want in Gothem. But as he takes down bad guys and gives more and more of Gothem back to the public, he becomes a sort of iconic hero for them. People start rooting for him.
After Batman has stopped enough criminals to get him to where Bane wants him, and then he pounces.
I think the final fight has to be in the Batcave. Alfred tries to defend their home but is taken down. Grayson tries to intervene but is stopped by Bane.
Now its just Bane and Batman. They fight in a vicious fight.
Bruce has no belt at this point but he uses everything on his suit, the blades on his arms, the ears, even the cape, and all those things get broken or removed as the fight moves on, It ends up just being Bruce in the armor suit from the first film.
Even several boobytraps in the batcave would be triggered during this final fight. To help make it seem like without the inteferences from Alfred and Grayson and the Batcave, Batman would be no match for Bane.
In the end Bane is almost winning and tries to break his back,
But Batman prevails, hopefully the audiance would be so much on the edge of their seat as to what will happen to Batman that when he does win their will cheer and be releived.
But Batman is SOOO drained that as soon as Bane is out, or maybe dead, and he is sure of it, and Alfred and Grayson are up and safe, Bruce passes out. Maybe the audinace might think he is dead.
But Batman does recover after a few months. While he was out of commission Grayosn has filled in for him. but Batman still wants him out, but after a scene of convincing Bruce he tells Grayson, with Alfred in the room as well, that if he is going to fight out there he better learnt o do it right. Or something to that effect.
Maybe even have Gordon meet Nightwing at the end or something.
But the main idea at the end is that the people of Gothem (and the audiance) knows that Batman isn't just some guy in a suit who decided to stop criminals in Gothem,
Batman is the sworn protector of Gothem and no one is going to stop his War on Crime.
I mgith have Grayson in a later sequal, but I would probably just have him in the spin off right after this film. Set it up that after a while Grayson wanted to move out of Gothem and help another city, start spreading Batman's War on Crime further than Gothem.
So thats what I would do. I just would want to see Nightwing before Azreal. But thats just me.
That was just my idea that I got from reading yours. Not saying yours was bad at all, I was just inspired while reading your story.
Plus these are just my own opinions, as is almost everything I post.
Oh, maybe a No Man's Land type story would work too, in a similar fashion.
I like your idea, its really veasable to the Nolan Batman world. I think it would work too.
Yours just inspired one of my own.