Ah, slight problem there. Don't FIFA regs say there must be opportunities for promotion to top regular season league in the region? If Bays, Western, Coa$tal and other MPL sides field a Div 1 team, you won't have any teams able to progress. Having said that most MPL teams want a quality Reserve league, right. Not sure how PDL fits with all this (was meant to be 'promising youngsters' league if i recall. But this hoary old chestnut has been kicking around for years...
Never read the FIFA regs, I thought it was up to each regions admin as to how competitions were administered including any promotion/relegation issues. As for no other teams being able to gain promotion you are forgetting Mid Canterbury, FC Twenty11, Cashmere, Waimak, Universities and Parklands, not to mention Rolleston who are on the rise as well. Bring in the newly merged Nelson team plus Richmond and/or Marlborough, suddenly you have 2 reasonable quality 8 team leagues and a much improved relationship between the Nelson/'Christchurch regions.