Personally, I think it'd be neat if they added another new mechanic in the same vein as Breakable Walls.

Gist is that these are door-sized holes shrouded in thick fog (no player can see through to the other side) that ONLY the killers could walk through. They do not need to be smashed or otherwise activated beforehand, they're just in place from the get-go. Killers would not be able to pass through these doors while in contact with a survivor (whether carrying them or Spearing them as Deathslinger).

I've been calling them Thresholds of the Devout, but I suppose the name doesn't really matter as much as what they could offer in the way of unique cut-off points/map traversal for killers.

To be clear, these are NOT portals, just doorways that survivors can't use. Ideally creating paths through certain walls on some structures and maps. I could see this adding a little more dynamic gameplay to maps like Midwich and Haddonfield (stick these in key spots along classroom walls or long fences).