Regarding nomad ships and who can use them, I think that it takes a special kind of nomad/human hybrid to fly one of these ships. A simple and unaltered host would probably suffocate inside the ship that was made solely for nomad use.
I would classify hosts into three categories.
Lesser Hybrid. Normal nomad control scenareo. Nomad ships would be restricted. Probably a politician, but still essentially human.
Greater Hybrid. You can't tell where the nomad starts and the human ends. Something akin to Taruvi. Closer to one lifeform than two. Nomad ships are usable due to modified essence as it were.
True Hybrid. Absolute cooperation and symbiosis. They are of both worlds and neither at the same time. The two part's are indiscernible. Really, theoretical in nature. Use of nomad ships? Can be disputed either way but unlikely because this is an entirely new life form entirely.
Pure nomad: Can use a ship. I assume ship bound nomads are more comfortable in ships than in people though.
Human. No, very doubtful. Suffocation and all that.
Also, are nomad ships calcium or lead or silicon or carbon based? Really, what do we know about that?
My character's research is more concerned about nomad psychology, not physiology, so who am I to say?
