I am still not happy over Elenwen being marked essential.
Spoiler
You can go back to the embassy after the main quest and kill her
I would love some DLC on the Thalmor as the game feels like they were originally planned to be the main enemy in Skyrim, then replaced by dragons and then a few months before release they decided to stick them back in. I think there are only 3 quests where you have direct contact with them but throughout the game, it is alluded that they are your enemies. Bethesda may have also done this as the want the next Elder Scrolls game to revolve around the Thalmor and they had to introduce them first.
I would love it if the first few DLC's were quite small but the last DLC brought together many of the loose ends(From the base game and the other DLC's) and you can decide the ultimate fate of Tamriel(Side with the Thalmor, Imperials, Skyrim, a DLC faction or seize power for yourself). I wouldn't be surprised if the DLC sent us to Artaeum or one of the other Summerset Isles.