It goes without saying there will be more Batman movies in the future, but the million dollar question on everyone's lips right now is when?. Unfortunately, the answer to that we dont know.
It seems many fans of the Chris Nolan Trilogy dont want to see the Batman on the big screen again anytime soon. Of course I loved The Dark Knight Trilogy, including The Dark Knight Rises, and certainly have them on a pedestal as greatest superhero movies ever made. That said, Id be more than happy to get more Batman, because I love the character and the world. As much as I love the Nolan movies I think there could easily be more of the character to explore; with a different approach and the myriad of personalities unused by Nolan.
I wont list this as something for the next Batman series to attempt because its kind of obvious, but the next movies should have an entirely different tone. For some reason people assume that when you say that you mean Adam West or George Clooney but Batman can be dark without being the realistic version we now know and love. For an example just look at the Arkham video games, they set a dark and serious tone but keep the mythical villains etc. This approach would be perfect for the next series.
So the following is 5 characters or story-lines I think a new Batman series could use...
I think this one is an absolute must. The Nolan Trilogy famously avoided Robin, Christian Bale regularly stating that he wanted nothing to do with the character, and then of course there was the ambiguous ending with John Blake using the Robin codename and inheriting the Batcave, presumably to become Batman. (It makes no sense for him to become anything else.)
Since the famous trilogy basically steered clear of Robin or any mention of sidekicks, it makes sense for them to have a major role in the next iteration of Batman. For years Robin has been considered a lesser character, for the more light-hearted versions of Batman. Possibly because people think of the 1960s pun-ridden Robin but the reality is the character is extremely important to the Batman universe and can easily be modernised, as seen in Batman: Arkham City.
Having already seen the origin of Batman, I think it makes sense to just start the first movie a few years into Batmans career and he already has Robin. That Robin should be Dick Grayson and he should be about 17, to set up a future storyline. By that logic Batman would be in his 30s, having been under the cowl for a few years, then recruiting Robin and Grayson having grown under the mantle.
The future storyline I mentioned would be that Grayson grows tired of being Robin and becomes Nightwing, which should either happen at the end of the first movie or at the start of the second, giving time for Batman to be on his own and Nightwing to become a hero of his own.
Eventually, (in the third movie), Batman would recruit a new Robin, Jason Todd.