It might work at sub-academy level as I indicated above - you basically create a single centralised sub-academy that acts as a feeder to the academies, with some limited 'first dibs' for the province that 'supplied' them to the national sub-academy. So academy level players are still training with the provincial squads, but the level below that is grouping together all the best players in the country and centralising the support for them. Positively it would have the benefit that if one province (currently Leinster) is churning out good players they are getting more evenly spread, but Leinster would still have some cherry picking of the best (currently), but the ones that take longer to mature etc could get a shot in another provinces academy. Negatively, you'd wonder would all the provinces be incentivised to develop their feeder systems to provide players to the national academy, or would they all just sit back and wait for the latest crop of St. Michaels lads to enter the system.
I really do think it would be a big retrograde step to lose the strength of the attachment/aspiration that young lads have to play for their home province