If we're talking about fuel for gasoline engines, probably the Bergius process would be more suitable, as that produces fairly high octane gasoline. It was extensively used by Nazi Germany for producing aviation gasoline, FWIW.

Fischer-Tropsch, while more widely known, is better for producing diesel and turbine type fuels.

Though the same basic objections you present are there for the Bergius process as well, capital intensive and consumes a lot of energy, so hard to imagine such fuels being economically viable.