There's always a discussion of whether or not Nolan's version of Batman can fit into a world or would allow for a world that also includes the Justice League as we know it.
While I don't think this is really the case if the studios were decide against having Batman in a Justice League movie or to have a Justice League movie at all since they can't utilize the Batman character; would it be more feasible to go the route of having an Outsiders movie instead?
That is, Batman in his time as fugitive following the events of The Dark Knight and the supposed third Bat-film decides that he does need agents who can work on the more murky edges of vigilantism and brings together a group of non or very low powered heroes to do this for him; guys like the Question and Green Arrow and Katana and the like. Would this make more sense to do?
Ultimately mainstream audiences might initially feel like they're being gipped out of seeing DCs biggest guns together on the big screen but any good movie can win people over.
I think Nolan's Batman would be willing, and maybe even glad, to join or put together a team of heroes to help him with his War on Crime.
I think the Outsiders would work as a Dark Knight spinoff, they have the same feel as the Dark Knight and could fit nicely without altering his world too much.
But
I also think that if Superman, and the rest of the JLA, existed in Batman's world that he would automatically put the group together.
He would see the potential for good they could do, not just in Gothem or America, but all over the world.
And the sooner the team got together, and the sooner they went to work, perhaps the sooner he could retire from his life as Batman.
Maybe even knowing they all exist would be enough to get him thinking about retiring.
But the idea that the Outsiders would be brought in might be intersting, especially if it were a TV series.
And maybe they would even be a precursor to the JLA.