The pacific island team needs to be able to recruit solid group of PI players. This means paying them a competitive wage so they don't get poached by NH and other Super rugby clubs.
Reality is that Super Rugby cannot afford to have a lackluster PI team just for development purposes. The Sunwolves are an experimental team, however they can fund their team to keep their squad together and more importantly for SANZAAR, there is huge Asian market to exploit pre and post 2019 world cup. Tv coverage in PI is very small and being rugby nations, already saturated.
However, agree that a PI team should be playing in tougher competition. The introduction of a Fijian team in the NRC is a good initiative. It can add a different flavour to the competition whilst also being competitive with less resources.
I think the NPC (ITM cup or whatever is called these days) should follow suit and include a PI team in the competition. This is the best way to increase development in PI and also maintain integrity in Super Rugby competition (mind you the integrity has severely decreased since the introduction of this 18 team format).