Is there an issue with RL fans turning off the game? Crowd numbers have grown for many years but of late a small falling off is taking place in the UK. I don't think the same teams winning is a problem. Compared to Soccer in most European countries, RL has no more of an issue (less in many cases) and Soccer has no problem with supporters turning up.
One difference is a in lower scoring game, a team of lesser quality can get a draw or nick a win against the run of play. The modern game of RL rewards the better side but that creates predictability and sport thrives on the opposite. What RL also has in SL is just 12 teams, possibly whittled down to ten soon. Most Soccer comps have 18 to 20 teams the same teams meeting happens less often. So seeing the same teams playing too often - with a likely outcome - isn't ideal. So what could help?
A few suggestions to possibly help:
1) Reducing the number of interchanges allowed in a game.
Adds fatigue later in the game that should create unpredictability.
2) When a ball carrying player is taken into touch, it counts as one tackle. Only on the last tackle it would count as a change over of possession. Either way, the ball is taken five metres in from touch and played.
Encourage players to chance their arm wider out and bring centres back into the game more.
A bit more radical:
3) Return to 5 metre defensive lines.
Attacking sides would have to stand a little deeper and go wider. Easy metres from dummy half would be harder to gain.
4) Reduce the playing number to 12 per side.
It could encourage more old fashioned ball playing skills with slightly more space in the defensive line.
5) Aim for 14 SL teams asap, with a goal to add more later.
The better Championship sides shows that talent is there. Talk of watering down standards is a red herring to me. People go to be entertained. If the games are open, less predictable, and have more variety with opponents fans will enjoy. More off shore teams will help with revenue streams so the money to each team isn't reduced. Earnest efforts to grow the media take and not have all the eggs in the Sky basket. If Sky walks away, diversifying will mitigate the problem or make it irrelevant.
The above suggestions used in tandem would be interesting to see how it would make the games less predictable.