Orson Scott Card wouldn’t allow a movie to be made if the script and character were written like that. It’s taken a long time to get that wheel rolling, and if there were stipulations such as what you mentioned, OSC would’ve told them to pound sand and look for someone else.
As for the disdain for Christianity, I remember his father being Catholic, but I think Ender didn’t want much to do with it. So there will be that in his character.
Other than that, I’m very worried about the movie as Gavin Hood, who also directed the X-Men Origins: Wolverine movie, is directing Ender’s Game. Now I don’t know if it was his doing that made the movie terrible, the writers, or Hollyweird, but I thought that was one of the worst movies I’ve ever seen. Nothing about it meshed with the first X-Men movie, and alone it was total crap.
If I recall, Card is a liberaltarian.
Thus, I don’t expect much defense of social conservative issues from him, except to the extent that they distort his storyline and plot.