I don't disagree, my thought was really on making the National a League Three and part of the Football League, I don't think that would work. That ignores how the pyramid works, and also that the National is fed by part time teams in almost all cases of the sides promoted from North and South...
But conversely make it harder for those part time clubs that get into the National like Havant&Waterlooville this season to compete. Balance to be drawn, the National has 4 relegated but only two promoted and you couldn’t add a tier below and expect those smaller clubs to travel nationally.