They are not going to deflate hype for upcoming projects by releasing information on a movie that's not even going to come out this year. We would still be waiting for the NWH trailer if that fan hadn't leaked it and they've revealed little since.
I'm fairly certain that Rachel McAdams Christine is going to be revamped and reintroduced as Clea in the movie. A multiversal counterpart of her being revealed as the daughter of Dormammu and a sorceress herself. Sam Raimi seems to be an old school Dr Strange fan, even referencing him in Spider-Man 2. I wouldn't be surprised if he decides to bring Dr Strange's characterization closer to his actual comic book counterpart.