In Diablo 4, I suggest that there should be different area characteristics that a player might utilize to their benefit if they were to figure it out. These mentioned characteristics can be about, but not limited to; the elites that spawn in there being more ferocious, traps that can be set by channeling altars, shrines being capable of refill when certain tasks completed, giant gates that lock some portions of the area for funneling attacks, untouchable gigantic magic wards zapping casters from miles away or cursing everyone in the area with Iron Maiden.
Shift and fuse different effects and different terrains, if player were to figure it out they should find ways to activate it before heading to the cleansing rituals. Engine is more than capable of handling all these effects. I at least wanna believe you learnt something from the previous installments and other ARPGs.
This is pretty much in line with my suggestion about D3 having a separated PvP arena mode. Sadly, I guess you decided to ditch D3 already and happy with current yardstick model so I have no other option but offer this to happen in D4 now. Hopefully D4 won’t have thousands and thousands paragon level accumulation of players to require any sort of filtering instead of a random match maker.
Besides a good randomization for such ground of hatred areas, I also suggest a puzzling placement for cleansing ritual areas with different area characteristic depends on monster level or complexity of the area. Every instance of creation must differ from the previous array of outlay by a small margin.