I sort of like that idea, actually. I think I read somewhere in an interview with Zack Snyder that now that the events of MoS made the world aware of an alien superhero, others would now come out of the woodwork to reveal themselves. A goddess--Wonder Woman, a human with alien technology--Green Lantern, and, of course, the human, Batman.
The thing with DC is most of their super heroes are alien or using extra-terrestrial technology, save Batman. Whereas Marvel is the opposite--all its cinematic superheroes are human--Tony Stark, Romanova, Hawkeye, or given superpowers via human technology--Hulk, Captain America--the one exception in their universe being Thor.
It's just that the Marvel Cinematic Universe is so far ahead of DC/WB's--there's Cap 2, Guardians of the Galaxy, Avengers 2, Ant-man--four movies all coming out or in production while the next MoS/Batman/Justice League movie is still casting.