Repose and Sleep have been pretty borderline useless throughout basically all of FFXIV with very minimal exemptions.
Meanwhile there's also a big demand to have healing checks be a little more engaging and creative, so...
What about if we add a feature to Repose that gives it the duel-purpose of putting living enemies to sleep while disabling mechanical ones. Then we include more adds in fights that can't be killed very easily and are meant to be put to sleep while other mechanics are in place to remove those adds?
One example could be some damage resistant creatures who you put to sleep, and can then be fettered by another teammate to have that add removed from the fight.
Another could including floating turrets that will do high damage to the party, but if you Repose them, they stop working and crash on the ground?
Just to be clear, I don't necessarily mean that all dungeons and raid bosses need to have these situations, but that the need for Repose graduates to being an occasional mechanic we can expect to see throughout the foreseeable future.