For starters the writing is fantastic. I've already acquired grand adventurer, and I'm still questing.
The monster mechanics I especially appreciate in this zone. For one, all of the world bosses are very well done. What truly surprised me was the Ox-Nix though. You have no idea how happy I was when I saw this monster immediately pounce at me, and knock me back; and furthermore if you allow it to live long enough is does some awesome AoE abilities.
This is what I want from this game. I want aggressive monsters that can convince me that they want to tear my face off. What I can't stand about the PvE in this game is how the grand majority of adds in this game (and a lot of bosses) spam light attacks with an occasional charge attack. My only gripe about the Ox-Nix was its low health pool.
The music in this expansion is also spot on. I would like more dark ominous shoes in the future as well. One request though, can we please change up the combat music to something more aggressive, and epic?
And finally the delves. These delves look phenomenal! They're not the copy-and-paste delves that we're used to seeing in Tamriel. They're huge, and intricate. I actually took a moment as I was going through one to check out the scenery.
ZOS, please continue to create such high quality content in the future. And more aggressive adds like the Ox-Nix :-)