Oh, and here's my ideas for a follow-up to Man of Steel 2. It could be considered a Trinity movie, but will include other characters:
Batman and Superman have settled their differences in MoS2, just as everyone expects, and have agreed to work together.
A Wonder Woman origin story would preferably come before this. A Flash origin story could come before or after, as his involvement in this story is optional.
Themyscira and Atlantis both exist on this universe's Earth. They've both been masked from humanity's detection, using forcefields, for centuries. Themyscira and Atlantis have an uneasy relationship that is bordering on war. Both civilizations were founded by ancient gods (Ancient Aliens), who maintain at least a minimal presence. Aquaman and Wonder Woman are both human/alien hybrids, or genetically engineered creations. Aries (possibly in collusion with Sinestro and/or members of the New Gods) is actually behind the increased hostilities between Themyscira and Atlantis. The increasing hostilities lead to confrontations that compromise the force fields that hide both civilizations from humanity. Hal Jordan is among the fighter pilots sent to investigate. This turn of events has also attracted the attention of Earth's Green Lantern, Abin Sur. Both Hal Jordan, and Abin Sur at some point, end up crash landing on Themyscira, or nearby. Hal ends up acquiring Abin Sur's ring, and is captured by Amazons, not necessarily in that order. Batman and Superman are both dispatched, or voluntarily resolve to step in to resolve the situation. This leads to confrontations with Wonder Woman and/or Aquaman. Eventually, the future Justice League members work together to take down their common enemies. These events set the stage to make Earth's heroes aware of a greater threat from space. In light of this revelation, a redoubling of Earth's defenses ensues, hence the introduction and expansion of the Justice League.
The stage is now set for Green Lantern, Aquaman, and Justice League movies.
I figured it would be best to launch Wonder Woman and Aquaman in the same film, or at least have an interrelated story, so they don't have to spend more than one movie explaining the idea of two different lost civilizations at sea that no one has ever known about. They could even put them both in the Bermuda Triangle to wrap it up a little nicer. Plus, the Ancient Aliens angle ties them both together well, and can be expanded to include Shazam and Black Adam later on, as Egypt has always been a hotbed for Ancient Alien myths. This also works well with the established world of MoS, which was a completely realistic world, other than the alien involvement.
Hal Jordan's involvement is optional, as I kind of have him filling in for Steve Trevor (see the 2009 Wonder Woman animated origin story). I also figured you could do a nice little nod to Wonder Woman's invisible jet by having Themyscira defended by fighter jets equipped with cloaking devices. Also, I figured it would be a nice way to relaunch Green Lantern and still use Hal Jordan, while maintaining a healthy distance from the Ryan Reynolds film. I do take a few liberties with his origin, him being a fighter pilot rather than a test pilot (he could be both, I suppose), and also having a direct involvement in the events leading to him acquiring the ring, rather than it seeking him out, halfway across the world. Also, this would give Hal and Abin Sur a little 'war movie' bonding time, and allows Hal to visibly earn the ring by helping a wounded Abin Sur through a war zone and saving his skin a few times before Abin ultimately succumbs to his injuries, and passes the (well-deserved, by that point) ring on to Hal. Plus, it would give us a more mature, responsible, heroic Hal, who is actually more believable as an experienced, accomplished, military officer, rather than Reynolds' immature, man-child portrayal.
Thoughts?