[@RandomCerebrate] Well the zerg overseer sounds like a character you can use as a crew. There's no real minimum to how many crew members you need to have. As long as you can make it work with the in-ship interaction with just one crew, you should be good.
Even if it's too short you can still post it here for now and edit it as you go. That way we can also offer feedback on what you could expand on if it's indeed too short.