To the contrary, I think the impending switch to an independent A-League will delay any thought of promotion/relegation involving NPL for years. It will however make it easier to allow for an expansion if moneyed up clubs are able/keen to join the new league, be it Canberra, Wollongong, Townsville or Auckland. This has however nothing to do with promotion or relegation in the sense discussed here.
Yep, pretty much this. Pro/rel, especially in connection with state league clubs, would be a huge risk for the independent league, and especially smaller clubs in the league (including us). And most of the NPL sides wouldn't have the financial clout and commercial backing to bring significant value to the league.
Even with expansion, the independent league will have to be careful. There really needs to be a broadening of the player base, and changes to the import slot rules, and eventually, the scrapping of the salary cap to ensure that the league can grow in a financially sustainable yet commercially attractive manner. It'll be a difficult balance to strike in the first few years of the independent league, and I don't imagine that there'll be a rush into expansion unless someone comes along that genuinely ticks all the boxes (unlike the FFA box ticking exercises).