> and that runs into the problem of having many people in a small isolated space for such a long period of time. I think the largest crews we've had up there were around 10 people.

Challenges of low gravity aside, this doesn't seem that different to a modern submarine. We have nuclear submarines with crews of ~150 that stay submerged for months at a time - the navy has to have some idea how to address the cultural problems inherent in packing 150 people into a tin can...