I reckon putting some more money into a 2nd XI (but give it a more appealling name than that) competition, where players can make at least the best part of a living from it and compete at a higher level than district cricket would be the way to go. NT and ACT could be in that (realistically, the ACT does not have the population to support a team, it would perpetually be a team made up of interstate recruits plus only a few locals - the Raiders have been in Canberra for a long time now and still struggle to stay solvent).
It wouldn't dilute the FC comp, but would give the additional opportunities Berry correctly identifies as being required, as well as given the best players not playing FC the opportunity to play against each other. That's 8 teams - one for each state and territory - assuming squads of 16 that's another 128 players who could make some kind of living from cricket. The salaries would obviously not be as good as FC, and realistically wouldn't be enough to support yourself solely, but they would permit the players involved to be semi professional.