There needs to be more random elements in dungeons.

Dungeon maps can shift. Mobs can change and jump out of nowhere depending on an innumerable amount of actions that you've taken. Killing a certain mob first and getting to a certain part of the zone at a certain period of the time, with a certain ilvl, while during a full moon, causes a change to the zone for the rest of the raid and the boss has different armor and a different set of attacks. Multiple that possibility in each area so that each dungeon has 3 possible maps that have so many prerequisites that it's nearly impossible to choose which you go down. It just happens.

Incorporate danger by "randomizing" elements that force you to pay attention. Provide thrill by making death a possibility and incorporating consequences for death.

I'll give it a name.
Final Fantasy XIV's Reaction Trigger Environment