Despite a global box-office haul of $865 million, many considered Batman v Superman: Dawn of Justice to be a disappointment. Mainly because when marketing costs etc were factored it, it like had a budget of around half a billion dollars.
Warner Bros. have bet big on DC and have a huge slate of films anchoring the next few years at the studio. One of those is the upcoming Justice League which has been filming for a month or so already with Zack Snyder returning to direct.
Now Deadline are saying Ben Affleck has had a creative presence on the film upped considerably and will now be listed as an Executive Producer, with his role (outside of that of Bruce Wayne and Batman) seen to help Synder shape the universe. It's a lot of characters, so if people thought Bats v Supes was cluttered, this could make things even messier.
Affleck is a pretty great filmmaker. While he won the Oscars for both Good Will Hunting and Argo, Gone Baby Gone and The Town are two extremely accomplished films who show a helmer with an inherent clarity with the material. It can only help Synder, and the proposed Batman movie that Affleck will direct at some point.