Seems to me an enterprising airframer (my previous employer forbade that noun, declaring it derogatory) could produce a light twin especially as an in-flight simulator. Its cockpit should roughly replicate a modern jet (hey, they're all alike, eh?). The IP could have a hidden "automation kill" switch that could quickly place the student in a degraded cockpit - in a real airplane that costs far less to operate than an airliner.
Or has someone beat me to this idea?