Adding something like an Emergency Mission to PotD or future deep dungeons could be a cool idea to help break up the monotony. By "Emergency Mission" I don't mean literally Diadem's Emergency Mission, but just something randomly present or not in any given run that can be encountered on any floor, that is rewarding, and that is different from the rest of the dungeon. It would maybe need to give a good chunk of extra XP and an aetherpool flare for both weapon and armor to interest everyone, but it should be something that's sufficiently desirable that it's reliably cleared/attempted when it's encountered.