The problem here is that people are letting the comics influence how things should be interpreted on screen. Ignore the comics and think about it from a film perspective. Lets say Man of Steel is a 100% original creation, Superman is a brand new character, that's the perspective you have to come at it from in order to expand the universe of that world. Now you want to add a new character in the second film, a beautiful woman from a mysterious tribe who has similar powers to Superman - how do you approach it?
If Wonder Woman were theoreically also a 100% new creation? She wouldn't be an infected Kryptonian. She'd be a bona fide 100% Kryptonian who landed in the Scout Ship 20, 000 years ago which is why there was already a pod opened inside the ship.
Thankfully, neither of those happen to be the case.
Oh, how I wish you were working at WB.
I've always been of the mind that fans have the best broad ideas, but terrible full formulation of them, so I really appreciate the comment.
Martian Manhunter also has the potential to bring in allegorical themes for racism. I read Lex Luthor: Man of Steel a couple of months back and one of the ideas in that book is that people trust Superman despite being an alien simply because he looks human. Obviously that Superman won't be as trusted in this universe as in the comics (pre-New 52) but there will be a level of trust the general public has for Superman at some point (the military has it already to an extent). However, Martian Manhunter would be looked at in the same way people would look at Brainiac and Darkseid, and would suffer discrimination due to it despite being arguably the most peaceful JL member. He would serve as a great allegory for racism and for the fact that humans only look on what is present on the outside instead of the inside.
That's an entirely brilliant idea, one I would love to see incorporated into a JL film, Superman and J'onn are near enough identical in terms of origin and nature, they're both
walking weapons of mass destuction, but one is held to a greater standard, the representative of humanity, the other the subject of distrust and hate, purely because of his visage.
How would you say Batman would impact "the general public" in your pitch?
Batman's usually the hardest to incorporate into the shared world. It would go either of two ways, both begin with people genuinely believing Batman to be some sort of monster (given all the other goings on it doesn't seem that implausible), however, in contrast to his usual depictions, Batman could act as a reassurance to people because he elevated himself through sheer mental fortitude to being able to stand amongst gods. But on the flipside he could also appear the least human, he essentially has willingly turned himself into the darkness of humanity and is now a trusted confidant of the most powerful beings in history.