Some airlines do cater for the business traveller Lufthansa operate a 737 between Frankfurt and Newark with 48 seats - all of them business, IIRC 30 need to be filled to turn a profit.
Seems there is a demand for customer specific travel options, you just have to pay for it.
Air travel in general has become a regular event in peoples and families lives whereas the fundamental design and layout of aircraft has remained the same - time for a change?