I had an idea for a dungeon mod that's kind of inspired by WoW's dungeon raids. It does few things...
1.) It makes a minor alteration to the bland vanilla box-like dungeons by adding a door to these dungeons. As if the vanilla dungeons are nothing more then just an entrance to the bigger dungeon itself.
2.) When the player goes into these doors it takes them to a separate dimension that has a randomly generated themed dungeon (swamp, jungle, desert, etc.) in it with puzzles, traps and a themed boss mob at the end.
3.) I picked the idea of putting these dungeons in a separate dimension because while in this dimension the player is not allowed to destroy or place blocks. This is to keep players from just cheating their way through the dungeon by mining their way around obstacles.
4.) There can also be special items that reveals secret of the dungeons. Like a rouges Spyglass that reveals hidden markings that clue you into hidden doors or hidden traps. Or even armor and weapons with randomly generate stats.
5.) Chests will be randomly secured by locks. This is inspired by Melonslise's Locks mod. Where there's a little minigame to unlock them. You could just do an integration with that mod. But I'm pretty sure the most update version of that mod is 1.16.5.
I just wanted a way to add more challenging ways to adventure in minecraft. Mojang has woefully neglected vanilla dungeons, and the end for that matter, when it comes to updates. And I feel like other modded dungeons just throw loot at players. Making it way too easy for players to get geared up. I want it to be more of a challenge.