Ozy
You are aware that there are lots of commercial aircraft flying around with one pilot?
The fact that they are smaller is entirely irrelevant to the workload of the pilot, or the difficulty in making systems to help.
I will predict that the route to unmanned will be:
Further autonomous small aircraft/helicopters fielded in US/western military.
Autonomous Combat UAV in western Forces.
https://www.youtube.com/watch?v=kw3m7bqrQ64
USAF Strat Cargo Unmanned.
Once sufficient evidence of safety is established,
FEDEX etc start Unmanned
Once greater safety than manned established,
http://www.baesystems.com/magazine/B...%3Dajf4vwvjv_4
Airlines unmanned......
Pilots flying planes into the sea/ground deliberately will only help speed this along.