You can also kind of split the beast a bit with development.
The national body could control development to a certain point, and just spit calling here say year 12... fund a national H/S football competition (get it televised to add to revenue), where players in year 11-12. We're talking 17-18 y/o's. Force these kids to stay in school and complete year 12, add some criteria about behaviour and academics to be eligible. Prioritise their education at a basic Year 12 level... national comp (the structure of that could be any number of things), televised, NRL teams can send their development coaches and scouts/coaches to these games, or watch them to assess players
Now that'll create super schools for sure, where talented players all end up in the RL power house schools to make sure they get noticed etc. But that's fine, growing up Blacktown Workers and St Doms in penrith were basically that anyways lol
Then draft from that pool. The players go to their clubs, and now the clubs have to continue that development through NSW Cup... sure the very best are going to quickly get into FG, probably within a year or two... others, just like now, might take 3-4 years and debut at 21
That's a lot of development too. It's not as if development stops at a draft.
And it would only be 2-3 rounds per year, so the players undrafted can then go to whatever club that wants them. Those drafted would be compensated with a pretty spicy pay packet to go to the club, and those who arent... well they get what they get.