Yes Wally, the hardest part is selling the concept so that there will actually be people who fly on pilot-less aircraft. Airbus is on record, calling upon the airlines to "sell" the concept because they are happy that they can build them, ie, they know they can't sell it themselves so they are trying to shift the workload onto the airlines. The technology for driver-less trains has been around for more than three decades yet there are very few of those in service today - passengers still want human beings looking after their interests when travelling.
I'm convinced that the new Multi-Scan radars in service now were designed to confirm the technology for use on a future pilot-less aircraft in that it does an evaluation of the weather and only displays it to the pilots if it considers it to potentially affect the aircraft. As we know, this radar system has many flaws and can't be trusted by pilots and thus, many years of research and refinement is required before it could be assessed as safe to use on commercial pilot-less aircraft.
I believe that the pilot training schools should keep going at maximum training rate because I believe that the school leavers of today will still be able to have a full career in aviation.