Flifth looks interesting, I haven't read the book it's based on but from what I gathered James' character in it is an, er, absolutely filthy S.O.B. Looks like a gutsy choice of role.
I also loooove Jessica Chastain, so a double film with her and James sounds good
I know nothing about Assassin's Creed apart from the fact that my brother was quite obsessed with playing it for a time, but I'm a sucker for medieval stuff so hopefully it turns out to be decent. There really hasn't been many decent historical (or quasi-historical) films lately.
I really look forward to the FC sequel, but I honestly hope that Fassbender and McAvoy do a film together outside of X-Men, their chemistry is just too good not to use over and over again.