I agree that the travel would be too if games were played daily so sticking to traditional 2-day 7's tournaments seems better. Nominating tournaments to be part of a league seems the way to go about that and making a trophy. There is no reason that only NRC teams or that even all NRC teams need to enter the competitions. Having NRC and ARU support gives the tournamants more legitimacy. Prmoting the fun in the sun, family atmosphere and having multiple levels of competition from seniors, womens, mens, u20s, and allowing international and club entries makes the tournaments better.
The Coral Coast in Fiji has had entries from USA and German national teams in recent years.
In the past international club entries to 7s competitions were based on finances and not that scientifically based. If there were a group of 4-5 major Oceania tournaments for clubs and invitational teams then these entrants could be more correctly chosen if countries like NZ, Australia and even SA had their own leagues. The top 2-4 ranked teams in each country could be invited to contest regional tournaments in Oceania (Coral Coast, Central Coast, Queenstown Sevens, Malaysia Sevens) en whilst their own leagues are still continuing until the end of January