As much as I'd like to see it, I can't see that happening. It is far too simplistic, and ignores offshoots like Rugby 7's, Girls/Womens rugby, and as @S'up mentioned leaves gaping holes at the Yr12 and Colts into Academies.
The rest of the rugby world seems to have moved or be moving toward a setup where Under 18 and Under 20 rugby are seen as the major stepping stones on their "pathways". Our development model/pathway must feed into those. U17 JGC is technically a good preparation vehicle to identify and filter kids into the U18 programme (rather than a Aust Schoolboys programme), where some serious development effort can be applied to the squad members.
There needs to be an entry point for those late developers, or code changers post Under 17's if we are to be seriously competitive at Under 18 and Under 20 level.
Hopefully this is stage 2 of the JGC revolution.
There will need to be some egos broken to rationalise the various schools and junior club representative programmes. Good luck there.
Some serious though needs to go into the Academies Programme as well, because it all seems rather ad hoc and subject to fairly regular fundamental changes.