Unmanned won't work, due ATC coordination! Forget reduced separation for increased movement rates, it will become like unmanned trains we see in terminals. Strict separation, no shortcuts, follow the flight plan line. And thats in the air, let the fun commence on the ground!
Long haul single pilot ops, that will be interesting.
"Its time to take a rest Dave.....but Hal there is weather ahead and reports indicate a rough ride. Dave, its time to take a rest to meet regulatory requirements, you must listen! But Hal......"