I'd agree with Dane, I think. Let the expansion areas bid for low-drawing games from across all teams; and build up an identity of their own alongside these games to set up the potential for their own team one day.
Playing trial games there would be a good start and it won't disaffect membership packages.
They shouldn't have to bid for games the NRL should help them to get as many NRL season games (not trial games) as possible until they have their own NRL team, and the SARL should be involved in the process as much as possible and should be using the opportunity to raise awareness for local RL by having their own brand marketed through these NRL games as much as possible.
The NRL should be pumping as much money as they can afford into the WARL, SARL, TRL, NTRL and VRL until they all are as powerful and have junior systems as successful as the NSWRL, QRL and CRL.
They should also be coercing the SARL (and maybe others) into preparing a bid team just for the publicity and rallying power that goes along with one. Give the people a cause (or an injustice to fight) and they will come.
Unfortunately as has been the case for the best part of 20 years the powers that be seem to be to short sighted and unambitious to see the importance in having a tangible presence in the non heartland states and territory.
While I'm having a rant they should also be taking the pressure of running the CRRL off the Raiders (the only NRL club that almost completely runs the local RL of their area) by setting up a ACTRL that is separate from the Raiders to mange RL in the ACT and surrounding areas, the Raiders simply don't have the time or the resources to control the running of RL in the ACT and RL in the ACT is suffering unnecessarily because of it.