Avoid diluting the player base too quickly?
Fair point. I wouldn't mind if the new teams were propped up with imports though. There must be plenty of bona fide talent in Europe and South America that would be interested in playing a season here, not to mention the Pacific Islands. It could have a dual purpose as a development league for international players at the same time as an elite league for local players. Those two objectives could merge together at about the same level of play and hopefully it would be a win/win.
Get guys like Hudson to use his contacts at Chelsea to send some of their prospects out to the south seas for a year. Seriously, NZF could act as a broker to put players in touch with clubs. Maybe NZF could take the risk to fly in a whole bunch of players in pre-season, organise a couple of trial games, and then run a formal draft system to assign them to clubs. On an annual basis the clubs would take turns at having first pick, second pick, etc. This would overcome the problem that the clubs may not have extensive international networks or be willing to take a risk on an unknown quantity. NZF could absorb a bit of that risk for the clubs and put their network to good use.