Such a spectrum would not be particularly useful for describing the behavior of politicians or voters. Consider that someone who usually votes for a democratic socialist party might sometimes swing further left and vote for a communist party, or further right and vote for a liberal party. But they're unlikely to vote for a fascist party. This fact is captured by a left-right spectrum, but not by the spectrum you're proposing, which would suggest equal likelihood of such a voter supporting a communist or fascist party.