What makes a good dungeon?
I'm writing my first litrpg, and so far I've only had the cast go on two dungeon runs. The first was a boss dungeon, so it only consists of them going inside and immediately fighting a boss. The second was a maze of square rooms laid out like a grid, with the door to the next room opening when they either kill all the monsters or solve whatever puzzle it gives them. I know it's not that interesting, but I skipped to the end after a few chapters so it wouldn't feel drawn out. The story is more focused on character development than action at that point, so hopefully it all balances out.
I'm worried about future dungeon runs, though. How do I make them unique enough that the reader won't get bored of them, and they're not just one fight after another with a boss battle at the end? It's going to be a while before they go on another dungeon run, so now's as good a time as any to start taking notes. What do you think goes into making a good litrpg dungeon, and what should I avoid?