Honestly, i think it would have worked in 15/20 years if Ledger was alive. But not so much now. No Joker (unless Nolan warms up to the idea of recasting since the character would be so much older), no Superman, no brief Two-Face appearance.
How would they construct a story? I guess the difference would be that the film wouldn't begin with a brooding Bruce in Gotham, looking to die in the cowl. It would probably start with him in another country, older, happier, and something brings him back. Blake's death during "duty". The future of the symbol being in jeopardy and a nutcase on the loose. Which would only work if Joker was present and say a young Dick Grayson was being mentored by Blake, but is now left alone due to his death, so Bruce has to make everything right.
That's the only way i can ever see it happening. Fan-fiction or reality.