Jared Leto enjoyed playing the Joker in Suicide Squad so much that he wants to keep playing him in future DC films. During an interview with the Toronto Sun, the actor expressed his hope for the character saying:
“I hope it’s an introduction (of the Joker) … and not the end! Because I could easily just play the Joker a couple more times and then retire. Because it’s so fulfilling and so creative and it’s so imaginative. It’s really difficult to think about doing anything else!”
One of the DC films he really would like to be a part of is the Batman solo film currently being developed by Ben Affleck. That's the exact movie that I'd hope to see the Joker in next. It would be a shame if he weren't. Leto goes on to say:
“I think it would be incredible to see Batman and the Joker go head-to-head! This Batman and this Joker. I mean, I don’t know, that might be too much! But that would be fun.”
We've previously heard rumors that the Batman film will be set in Arkham Asylum and that the movie will be packed with villains. If that's really the case, then the Joker would have to be among them, and possibly be the one who leads the revolt against Batman.
I any case, I doubt that Suicide Squad will be the last time we see Leto's Joker in one of these DC films. I'd say it's a safe bet that he'll pop up the next Batman movie, but we'll just have to wait and see.