2. Smaller fun additions:
-Rooms without enemies, but with icefloors and several obstacles placed in the room, so you have use your head a bit to make it to the exit. (Implement a handfull of different patterns as to where obstacles are placed, for any kind of room => referring to the setup of the entrances/exits)
-Optional objectives: For example: A device/item with a sealed entity or group of entitys is found within the Deep Dungeon. You can decide wether to leave it, without any harm done, or do the extra objective for some form of extra progression on your gear, something like the gems in suggestion 1 or something along those lines.

This were some fun ideas I came up with, which don't nescessarily have to be added to the game, I just think it would be fun if some of them would be.

I think this kind of change would be really fun, because it would, just inside Deep Dungeon, give us a way to play our jobs/classes, but with a different layer of paint on em, so to speak.