My first reaction was against the idea, but you bring up some good points. Obviously, specialties that require specific lengthy training or certification couldn't be filled this way, but many management jobs could easily be. As a former MSG type myself, I can tell you that very little of what I, and many of my counterparts, did required a specific skillset. The most important things were a basic understanding of the mission, decent leadership and admin skills, the ability to read and interpret the AFI's that governed your job, and most especially good NCO's.
I would argue that mid-level rated Captains would make great flight commanders in places like Supply, Vehicle Ops/Mx, Security Forces, Base Comm, Services, Force Support, Aerial Port, POL, Aircraft Mx, etc... Arguably, rated Majors should easily fill similar DO positions and possibly even squadron commands. If you're proficient at your operational job, there's nothing wrong with filling one of these positions and stepping to fly from there. It would, however, require a fundamental shift in our cultural paradigm.