Flashpoint
Yes, we know that Flashpoint is an alternate timeline with Thomas Wayne as Batman and Martha as the Joker, so settle down, Susan, and hear us out for a second. Knowing how things have panned out so far, the forthcoming Flash film, Flashpoint, will probably deviate from the source material and provide the opportunity for a soft reboot of sorts.
If you think about it, it’s the perfect way to introduce a younger Bruce Wayne/Batman into the DCEU due to the effects of Flashpoint as well. Say Barry has done all he needs to do in the other timeline and jogs on back to his reality, but causes a ripple in time and boom! Suddenly Gotham City and Bruce are taken back a few decades because of it, leading to a possible Watchmen-influenced storyline in the future as well. We already know that New 52 took 10 years from the characters’ lives, so it’s entirely possible the film universe will explore a similar concept.
At the same time, this could also fix the big Joker problem and remove the stupid tattoos and Ace Ventura mannerisms from Jared Leto’s character. See, a soft reboot doesn’t always need to spell bad news or the end of the world for a universe.