And this is why there should be a draft, as salary cap limitations prevent us from doing what you are prescribing. It would give us a chance to get top prospects for next to nothing and not be reliant on our own backyard. In the US, rookies are on a much lower pay scale for the first 4 years so you can build a roster around them with a budget in mind, eg a quarterback, which would equate to a top half in NRL.The team is always going to have kiwis in it on the basis of being a team based in NZ.
The point I'm making is that theres no point in signing 'kiwis' just because this is a kiwi based team. You should try to sign the best player, regardless of where they come from.
Also, when your own backyard is being pillaged by the likes of the Roosters who take the cream of the crop, it gives the bottom teams a better chance at being on more of a level playing field as they get first dibs at the best players in the draft whereas the top teams get last dibs.
With a draft format, we might be able to draft a top local prospect that would otherwise been picked up by a Sydney team (using the current format where recruitment wins).
And if a team is intent on getting a certain player in the draft, then you get the fun game of teams trading to move up the draft to get their man ( trading with current players, future draft picks etc), which can strengthen your team in the future. Its what makes a lot of the American sports like NFL fascinating even during the offseason.
An NRL draft may never happen, but one can dream.