The answer for the NRL isn't to relegate/promote, we can not afford to treat our clubs this way, if a club drops out of the comp, it usually come with losing that roster, members, fans and interest, i get that UK football has the lower teir comps, but no one watches the equivalent in Aus, its basically a breeding ground for reserves and rookies, it doesn't work the same way, and will effectively kill the participation of the area, north sydney bears and Newtown jets are the prime example,
Fair enough theres a heap of Sydney based clubs, so those two drop away, and its business as usual, but imagine if Melbourne Storm or Brisbane Broncos have to relegate, how do you have a comp that doesn't have them or the Newcastle knights.
And before you answer, one rule for all, there is no such thing as sydney clubs getting relegated, and expansion teams not... it will never ever come to pass