passengerless aircraft?
I am SLF and my only piloting experience is on hang gliders so I will not be too upset if modded.
All the what if? scenarios discussed above need to have been thought out by humans in advance, if the computer is to do anything useful. I worked for a small IT firm that was quite sure its systems were year 2000 compliant but reluctantly spent £250,000 proving it, only to find four bugs. Each was small and easily fixed but had they passed unnoticed, some of our clients (quite large building societies) would not have been able to do their year-end accounts. We did not even find all four ourselves during the testing, our customers found some of them.
If you look at advances in communications technology there is ever less need to travel for business reasons. My son defends cases in patent courts in Europe via video link. From 2014 on many of his business trips are no longer to Munich or the Hague but down the corridor to the video conference room.
That leaves travel for pleasure. With the diminution of cultural differences there is arguably less fun. McDonald's in Moscow is pretty much the same as in London.
If losing pilots saved 50% of costs there might be some point in it, but for 5% saving? I also heard, and there are doubtless experts here who can confirm this or otherwise, the additional insurance costs for single pilot business aircraft wipes out the salary saving of a first officer. Only perhaps OK if the same person owns the business and both owns and flies the aircraft.