I'm a supporter of the franchise system in RL.
In terms of commercial prosperity, it's light years away from football. The gap between Super League and the Championship is a chasm in terms of both finances and playing ability.
7 of the last 8 teams promoted to SL were relegated straight back down. Promoted teams scrabble around for players because SL clubs sort out almost all their contracts and new signings for the next season well before the end of the current season. You often see players released from the relegated clubs for financial reasons signed by the promoted club. And promoted clubs sign journeymen instead of bringing through their own youngsters as they think the journeymen give them a better chance of scraping staying up.
The NRL uses a franchise system, with all clubs having a de facto reserve team playing in the lower tiers, alongside smaller, non-NRL clubs. It works well.
We had a full franchise system for a few years and IMO it worked better than a promotion/relegation system as it provided stability.
This plan, incidentally, is not a full franchise system. But it does protect from relegation the clubs that meet certain criteria on things like stadia, support, finances, and running reserve, Academy and women's teams. These clubs would be Category A, and there'd also be some Category B clubs in SL. Cat A clubs couldn't be relegated but Cat B clubs could.
In principle I support these clubs (like Saints, Wigan, Leeds and to a lesser extent Warrington, Hull and Catalans). They invest in the game, bringing players through. But I hate halfway measures and the sort of complications this would bring. What if a Cat A club finishes bottom? Does no relegation occur? What happens to the Championship club expecting promotion? Does the lowest-placed Cat B club instead go down?
How rigid the authorities are with it remains to be seen. We had, in the early 00's, the 'framing the future' plan. This required minimum standards in terms of finances and, most importantly, stadia. Clubs were given a set period of time to get their stadia up to standard or build a new one. Every 'Lancashire' SL club did, sometimes making sacrifices and paying a competitiveness price. Then, when Yorkshire clubs like Wakefield, Castleford, Hull KR, even Bradford (Leeds got a free pass because they're the RFL darlings), the stadium requirement was quietly dropped. Wakefield, Castleford and Hull KR still have shite grounds (Bradford went bust and exist in the lower leagues)
There remains too little money in the game. And too many shit-arsed clubs who want to block progress in case it affects them.