Deep Dungeon primary purpose is generally to level up other jobs,

I used it to level up RDM when it came out so I could play Stormblood with the new job.

The format for that is perfect... the first Deep Dungeon though had a really good story to go along with it.

Maybe though... they could use some more flair to them. There are things that have been removed in ARR dungeons that I wish weren't because they were kinda cool. Like the Cannon fire in the boss fight in Stone Vigil, or Aether Voidlamps in the Hauke Manor.

The advantage to something like a Deep Dungeon that regular dungeons don't have, is that the formula can have curve balls thrown at you like that and they will never get old because it's entirely random what you would get. So unlike the Static Dungeons that could get formulaic... Deep Dungeons won't.