Enslaving all manners of humans with FLHook is a great idea, in my opinion, for all the reasons mentioned. It would work well for the kind of play TOME mentioned as well, destroying NPC ships and enslaving their pilots.
Using something similar for mining, however, doesn't seem to be very useful. If miners just convert ore to a metal right away, what will the ore ever be used for? Why would there be an ore commodity in the game? That discussion would be better suited to the Mining Concept Ideas thread, though.