Aquaman has made 1.1 billion dollars worldwide and counting. It has grossed more than every DC movie and more than all but six Marvel films. Unlike Wonder Woman it was a huge success overseas. Aquaman is now a bigger hit than Batman and Superman, and will get more exposure.
Obviously this will change their marketing, as Wonder Woman and Aquaman will be the new stars. I expect they will focus on using Batman less and make Superman lighter and more friendly to help imitate Aquaman’s success.
Not only will DC imitate Aquaman with current movie heroes, but this will make them more excited about other heroes getting their first solo movie. Maybe Flash will be the next Aquaman. Maybe it will be Cyborg or even Question. I think a Booster Gold movie could be a big hit. DC should stop viewing Superman and Batman as their marketable heroes and find ways to get their other stars to be movie hits.
This will also help to build the Injustice Gang/Legion of Doom/Secret Society of Supervillians. In the Stinger to Justice League they hinted at building a large group of villains to challenge the league, and I am ecstatic about it. In the animated Justice League my favorite episodes had the super villain brawls with around 6 heroes battling around 6 villains, and the MCU has not done this. There was no confirmation that Black Manta would join it, but he is good to go for future films and be a threat for multiple films. DC now has great villains in their films and I expect Black Manta will be one of the main physical threats of the group.