Re: How long should the new series go on for?
If a mod could put a poll, that'd be grand.
Anyway, I think the series should have a conclusion. If you look at what are often considered some of Batman's greatest stories are his origin, ending. That goes for many other heroes too, including Superman, Green Lantern and Flash.
Preferably, I'd like to see a 5 film saga (minus Justice League):
Film 1- Details Batman's early years with brief expositionary scenes of his origin. The main villains would be Penguin and Riddler, perhaps Red Hood could be a psychopathic small time gang/hitmen. Cobblepot acts as the final nail in the coffin of Gotham's stand against corruption, solidifying Bruce's belief for Batman.
Film 2- Set several years later, Gotham is now accustomed to supercrime. This would be the real departure from what has come recently in film as Bruce begins establishing his Arthurian legend with taking in Dick as Robin. Villains could perhaps be Deathstroke (the assassin who killed the Graysons?) with Two-Face as the main villain.
Film 3- Based on Arkham Asylum: A Serious House On A Serious Earth, as well as the two Batman: Arkham games. This would be a deeply psychological tale that explores whether Bruce is as much a lunatic as those he fights, hint towards Zur-En-Arrh. Dick has a reduced role and hopefully a Nightwing spinoff instead.
Film 4- Based on Jason Todd's various return storylines. Fairly simple really,further explore the idea Bruce is a dangerous madman, who endangers others.
Film 5- Based on Batman RIP. Serves as the conclusion to the series (or at least this era of creativity). Batman vs the ultimate evil. The ending would be like the closing panels of Batman #700 and #683.