DBWI: What if Greg Sestero hadn't been cast as Batman?

In 1999, two years after the disaster that was Batman and Robin, Warner Bros. and Joel Schumacher had decided to "go back to basics" for the Caped Crusader's next try on the big screen. Wanting to get something closer to Tim Burton's first two films in tone, Schumacher optioned to adapt Frank Miller's Batman: Year One, and recruited Kevin Smith (then known for his "View Askewniverse" films) as his co-writer on the condition that Smith would get to pitch his idea for a Superman film on his own creative terms. As if things couldn't get even odder, Schumacher recruited Martin Scorsese to produce the film. And as if to add a cherry on this strange sundae, Scorsese cast an unknown from LA, a young 21-year old by the name of Greg Sestero. We were all expecting yet another campy disaster as a final nail in the coffin to our beloved Bats. What we got instead was the exact opposite - a gritty '70s period piece heavily inspired by Taxi Driver and Falling Down in tone; in addition to Sestero as Batman, we got Billy Dee Williams as Harvey Dent (again), Gary Oldman as Detective James Gordon, Ashley Judd as Selena Kyle, and Robert DeNiro as Carmine Falcone. This was the beginning of the "Nu-Batman" trilogy (which added Daniel Radcliffe as Dick Grayson/Robin and Tommy Wiseau as the Joker in The Dynamic Duo and wrapped up with The Dark Knight, adapting The Dark Knight Returns) and with the Burton-directed Superman Returns, the DCMU.

So the question is: what would've happened to the franchise had the rousing success of Year One had not brought the franchise back from the brink? Honestly, I think that Nolan fellow who won an Oscar for Memento could've done a good job.