I think a fee market that is relative to demand for blockspace is perfectly reasonable... but not today. We're too small to sustain the demand in the face of countless competitors. Bitcoin doesn't have the benefit of the periodic table, if we don't capture share while miners are subsidized and incentivized to secure and process transactions... it becomes like rpietila's castle game, with you and a few thousand others trading pogs back and forth. (A scenario in which a 1MB block limit will be generously sized.)