It should increase the visibility of the league and therefore increase fans and sponsor attention. It will also increase the crowd size for those "derbies" because at least there will be more than a handful of traveling fans for once so we should still get those one or two one off games per year.
I'd also expect it to mean that other parts of the country get exposed to football that they wouldn't. If the Phoenix take a game on the road (even if it's because of stadium availability) they take it to Auckland at the moment because that's where the cash is. If there's an Auckland team they may decide to go to Christchurch and Dunedin.
I'd also expect it to mean that other parts of the country get exposed to football that they wouldn't. If the Phoenix take a game on the road (even if it's because of stadium availability) they take it to Auckland at the moment because that's where the cash is. If there's an Auckland team they may decide to go to Christchurch and Dunedin.