So, I'm wondering how one might go about some gaining of "interesting" crew members, beyond "the players are those crew members". Certainly, NPCs on my ship shouldn't outshine the PCs, even if I might not allow PCs some options (those will probably be obvious below), but you still might want to have some special crew members, and I don't know, entirely, how you'd go about finding them. The stuff beyond the simple Acquisition test, like what other bits (Peer [X]) you might need, in order to find, meet, and convince them. Some of these are not people you want to pull a gun on, and then trust to be loyal. So maybe some scenario bit you might use, maybe have used, where this idea isn't terrible?
NSP #1
You are journeying into space Man hasn't been through in ages. You decide to acquire an Eldar to guide you through the space ways, being the greatest stellar sailors there are. Perhaps an Eldar Ranger/Pathfinder would do well here. DE CAN be elicited to join, so maybe a CWE, too. You might want him long-term, but your money isn't so valuable to him. How?
NSP #2
You just recently clashed with Hadarak Fel, and thought that his silent servant with prodigious powers was a nice asset. You're out in the middle of benighted space, where enlisting a psyker could be hard, and many Sanctioned Psykers are crummy (you might feel; I MOSTLY say that for this, and because Astropath Transcendents don't seem like great Battle Psykers to me), as well as unavailable. So, you decide to poke around the streets of Footfall, or some other weak-lawwed place. You need to find, coddle, and enlist a "decent" Rogue Psyker, and all the perils that go with that. How?
NSP #3
You decide that some decent, but expendable muscle is needed. Whether it is to keep some distant observers from associating the acts with you, or simply knowledge of their capability, you decide to enlist an Ork warrior and some of his "loyal" Boyz. Maybe they want to get out from under their Boss, maybe they want to loot for you, and take it back to trounce their Boss, whatever. They could be good ground forces, decent boarders, and tough. Not a lot of upkeep (hardy and they heal), and no sad feelings if they biff. How?