This is the best cost and weight savings idea I have heard in a long while. I understand the benefit of having two brains in the cockpit. But does one of those brains have to be actually sitting in the cockpit? Versus sitting in a nice safe room someplace.
If the particular operation is just controlling a drone in the near area after launch, then probably you could get away with #2 being somewhere else, if you could solve the problem of secure, unjammable comms. But for a lot of other missions, at least with near term technology, the advantages of having #2 there are significant. For example, in NoE flight while suddenly having to engage a pop-up target off-boresight with the gun. Coordination between the two crew is going to be a lot more productive if both are right there. And of course if one of the crew takes a hit, it's nice to have someone there who can take over and get the heck out of there.
Now longer term technology? Maybe there may not be a need for anyone to be aboard.