the only problem i see with it is there is almost zero reason to do anything but NM zerg train

even the lowest level one is worth more experience than a chain 30
anemos crystals from NM are way more abundant than trying to chain for protean
you only get loot boxes from the NMs
and the random nostalgia drops are only from NMs

they really need to just put in some random repeatable quests in the hub.
"go find the sparkly point" or "kill X mobs" that give some exp/protean/boxes

i do enjoy the danger aspect of it and understand the accelerating nature of the grind. getting crystals will probably be super fast once you've done the grind once