I wish they would just allow us to go 5/5 on all the job-specific merits at this stage of the game. If they didn't just want to remove the barrier, it could be unlocked in the HP/MP category (since that has become a slight "catch-all" with the max. merit points in there) for 45 merits as a one-level unlockable that would allow job-specific merits to be 5/5. They could even add that "special touch" and make it two things to unlock, one for Group 1 and one for Group 2. Every BLM would have the ability to have 5/5 on all AMII, every RDM would have Paralyze II, Slow II, etc., which have been asked for multiple times as scrolled spells.
I would just think that, at this stage in the game, there's no reason to have to weigh trade-offs for putting one level in one job-specific item when a different one would have to suffer from the lack of that level.