Truly, and let me be both serious and sarcastic all at once, since SE is so fond of transient "alternatives" (that's pure Zodiac Saga/Tome Weapon salt right there), why not implement Expert Guildhests?

To avoid the hunt rewards imbalance/catastrophe:
-Offer gil, GC seals, and tome rewards, but NOT as much as a full dungeon run. Otherwise the scales would tip.
-Aside from first time runs, do not give a bonus or daily bonus. (The amount given should be substantial enough as is, again without outshining dungeons) The trade off is the speed and ability to repeat quickly, a la speedrunning.
-Be challenging, but without level syncs or materia restrictions.
-Perhaps shake up the party system? Minimum of 3, max of six?

Full dungeons remain viable for rewards/gear/items/tomes, and the speedrunning types get something to enjoy as well. Everyone wins, no?