Does zombies sometimes feel completed ?

I feel like all the maps from WAW to BO3 feel like they perfections of the formula and anything new they add beyond what they added in those games would feel boring and uninteresting then there's also custom zombies where people can make their own maps or iterations of the already well established formula from those games

Honestly I feel like zombies has hit a dead end and anywhere they go from here would either be boring and uninteresting or just not feel like zombies as we know and love

But I'd still be down for more zombies in cod games , but I don't want it to be based on or part of the treyarch storylines and gameplay mechanics