There is technically something like that already. Palace of the Dead and Heaven on High were meant to be "harder content" for a team of 4 if you go for reaching the higher floors. I wouldn't consider it savage level in a party but it can be a little nerve racking sometimes if you get bad spawns.

Really though, if they give me more content in general, I'd be satisfied regardless. This is starting to feel more like Droughtbringers.