Intricately hand crafted. Some kind of catch phrase going on here or something? I hear it over and over and it sounds like a bunch of people on a 3 AM infomercial waving dollar bills at some snake oil shyster. Haha. Did you guys even play OB and MW? The majority were incredibly vanilla and many didn't make any "sense". And why was it that every freaking ruin or fort in the countryside had been overruns by something or other anyway? Where is the lore for that? How would anyone in the country survive when everything is overrun with this that and the other thing. How would the people in the city survive without farmers? The countryside is apparently a tolkein style jurassic park, can't farm there.
While I agree at Oblivion, you're absolutely wrong with Morrowind. Each and every dungeon was a masterpiece of world art. You just have to look at the details, rather than the layout. They even cleverly used something so despised as "Leveled loot" to give context to the dungeon. You find Dwemer enchanted items in Dwemer ruins (And smuggler caves), stuff like that. That's even before getting into the finer detailing, like placing seemingly useless baubles (Lockpicks, cups, ect) in specific areas. For example, in One outlaw-theme cave, you might find one segment as the common area. Mostly low-tier stuff, clay jars, ect. But further in, you start seeing extravagant Limeware, high-quality clothes, expensive liquors, ect. And a reasonable connection can be made about the "Story" of the dungeon. ONe area is where the underlings were, here's where the head-honcho shacks up.
The fact that their work was wasted on your inept perception, does not make their designs "Vanilla".