Well, in theory I'd like four, but I'll probably only have two. I know DH strictly only wants two (something about replacement fertility...humph!) and in practice I probably wouldn't be able to handle more than three at max. Two would make me very, very happy.
If a boy and a girl: Ivo Marcellus for the boy, after my father and (loosely) after my maternal grandfather. For a girl, I would use something that begins with a 'C' to commemorate my mother. Cordelia Mathilde? Cecily Delphine? Cosima Lucette? Don't know.
A second girl would probably be Eulalie, a family name on my DH's side that I love. Eulalie Claire maybe?
A second boy, hmm, I don't know. DH likes Calvin a lot and if we don't have a girl already it could still honor my mother. So, while it's not my favorite name, I think I would use it. I also really like Marius and Remy.