When thinking about expanding the game, there is too much emphasis on the NRL as a tool. The state of origin used to play one game a year in Melbourne occassionally. Playing an origin game in say wellington would give the game an enormous success.
Australia vs New Zealand or Great Britain tests are always played in Sydney or occassionally Brisbane. Gold Coast, Central Coast, Perth, Adelaide etc would draw as good or better crowds than in Sydney and would give the game a boost in these expansion areas. The recent Qld vs WA match could have been promoted to the hilt. Perhaps give the WA side 2 or 3 Ex reds to guest stint and with heavy marketing, you would have a meaningful game in Perth that was capable of drawing a good crowd.
I think the QRL could be the key to expansion. They could take sides from Melbourne, Perth, Adelaide, Wellington, Christchurch or any other expansion area for a fraction of the costs of an NRL side. If the NRL helped these expansion clubs immensely with marketing they would all get the chance to have successful clubs in a great competition. This could then be expanded when and if the clubs gain a solid enough base and following to compete at NRL level.
