The Kryptonians have done nothing to endear themselves to the humans so far...not to mention the rest of the galaxy either. I wouldn't be surprised if there was some kind of big war between Krypton and Earth. The status quo has been changed pretty good with the Kryptonians, one that seems to be accepted widely by fans, I think anything else major though would serve to push them away. I doubt that Superman would have an affair with Wonder Woman. He loves Lois. Wonder Woman knows this and it I think succuming to any feelings would go against her Amazonian sense of honor and loyalty, not to mention sisterhood. It's a possibility though.