the pilot is more than just a pilot though. if a flight steward says something, chances are u wont really pay a huge attentuion to it. u would to a pilot
also its hard o convey all cockpit info to the pilot, such as cockpit views, turbulance, wind shear, visibility.....if u did devise a system to do this it wouldprobably be cheaper to keep him/her in the cockpit.
still what iof you had the ability to take control of the plane. on hijack the pilot hits a switch and it enables a pilot to remotely take control of the plane...maybe