Why can't we have dungeons with multiple paths/open areas?

[Ramien]

I'd prefer the dungeons be randomly generated each time with different each time.

Such as Diablos dream makes the environment change each time. And the monsters randomly chosen.

Maybe this time you need to defend a npc through a dungeon. Or puzzle dungeons with no fighting at all just solve random generated puzzles.

Do you really want to subject your dungeon experience to the tender mercies of the RNG?