Done with the DLC. Took ~10 hours.
I literally just came across only 2 side-quests (the ones with the green exclamation marks) throughout the 10-odd hours. I didn't use fast travel at all and flew on my mount in the hopes that there might be quests that I might run into, but nope. Personally, I'm okay with that, because then the main story gets a good amount of focus, which is pretty decent'ish overall. But, I can totally imagine some people having a meltdown over the lack of side-quests. In terms of the main story, I would've liked a little more emphasis on Nemesis, though (I promise, that wasn't a word-play).
The final boss battle is ace! The scale is mind-numbingly epic. Also, hands-down the best looking game out there. Visual fidelity at its finest. Nothing comes close. Not even GoW: R. I played in Favour Resolution mode and utilised all of those self-emitting pixels on my OLED to the maximum. What a treat!
The other "supposed" boss battles are kinda underwhelming, though. But the last boss battle more than makes up for it with its scale.
There are some minor open-world'y bugs here and there, but nothing major.