I don't really care for dungeons so 1 per patch is fine.
My problem is more about the extra dungeon being taken off doesn't necessarily trades for more content added in the game. Stormblood had four full fleshed Eureka zones (Bozja will have two by the end on 5.5) and Baldesion (comparable to Delubrum Reginae), and two more dungeons, and a deep dungeon, and more PvP maps I believe ? Most of ShB content was re-using in game content (Blue Mage, Ishgard Diadem).
Expert roulette has never been so boring with only two dungeons, that's another issue.