It’d also be nice if David Fincher would return to direct, but arguably the most important returning element would be Jesse Eisenberg reprising Mark Zuckerberg.
That way there’s still a sense of continuity, and since Eisenberg earned numerous accolades for his performance and has only become more famous since then, it’d be worth doing whatever it takes to ensure his participation.
Aaron Sorkin didn’t elaborate on whether or not he himself would want to write a sequel to The Social Network, although if he feels this strongly about such a project, one would imagine he’d be open to the idea of carving out time for it.