Might not there be a reason why those areas no longer support (literally) LOI clubs? While I don't really see the particular relevance of under-age football to Senior, mens football, since the big professional sides will still sign up the best youngsters from the provinces should they think them good enough
Anyhow as I've noted before, the building blocks for your pyramid must lie with your clubs, not regions, counties, Provinces etc.
Of course the club base would ideally represent a wide geographical spread, but football in Ireland has never worked like that*. So that with the exception of a number of clubs in what I call "proper football towns" (eg Sligo, Ballybofey, Derry), located in areas of the country where football is otherwise isolated, the game in ROI is predominantly urban and Dublin/East Coast centred.
Therefore you should concentrate on building your pyramid first from those clubs which already are organised, thriving and ambitious, even if LSL-centric, then build outwards from a strong base to develop the game in newer, less traditional areas**.
* - I think I read somewhere that when the IFA and FAI split in 1921, there were more registered football clubs in Co.Antrim alone than the whole of Munster, at least after the British Army pulled out. While Connacht can't have had too many clubs, either.
** - The fact that eg Kerry (county) has a population of 150k is pretty irrelevant, if most of the the people there aren't greatly interested in the game, and/or are isolated and spread out etc. But if an individual town like Tralee already has a solid history in the game, then a 25k population should be enough of a base on its own to build a senior club. Similarly, if Tralee were only, say, 20 miles up the road from Dublin, the same principle should apply, regardless of how many other big clubs there are nearby.
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