I was thinking it might be kind of neat to see your doffs, and perhaps the boffs not on the bridge, running around inside your ship. some of the doffs are kind of hard to get or expensive, like the tholians. those that are on missions should be gone if they are off ship, but they could enter the hallways occasionally as you are wandering around your ship. the extra Boffs would be neat also, imo, because you dress them and seeing a Breen on your ship wandering around would be cool, imo again (also no pun intended).
The idea is pretty much as old as the DOff system itself, and has even been mentioned by the Devs IIRC. I'm sure a lot of players would love it if the effort we put into creating themed crews showed up when the captain went below decks.
However; that would require, as a minimum, a significant rework of how the game populates shipboard locations. You'd probably need the equivalent of the fleet Uniform UI to record their uniforms, then turn the DOff portrait (back?) into a full head, and slap that head onto a body...
Point is it's not a trivial task to code and so will probably happen when they get around to letting players design their own interiors with the foundry. Read - never, as there will always be a more financially pressing thing to do.