Right, I'm running a GTX 1080 overclocked on a 3440x1440 GSync monitor and was initially still disappointed that past the wall of light in karnaca, it was dipping down to the 40s still, even when the adaptive resolution threshold was set to start at 60 fps. The one setting breaking the really big views is texture detail, which my card with its 8GB of Vram is struggling with. So, rather than auto settings which had most things on very high and textures on ultra, it now runs better with everything at ultra and textures on very high.
I also set the adaptive resolution to 65 with the quality setting on whatever the nicest quality one is called, and now I've got a massively smoother game than before. Actually feels as tight as Dishonored 1 now. Very happy. Can't wait to dive in properly tomorrow after work.