Are you using r_rawinput 1? In your bios is EHCI Hands-off set to DISABLED?
I had a similar problem. On my old PC (2600k/gtx770) I always used windows 7 but i tried w10 (i don't remember if it was 1607 or the previous version). Everything was fine, the mouse feel was the same but i rolledback to w7 because of some incompatibility with my old soundcard drivers. More than 1 year ago I changed my system (6850k/gtx1080) but i decided to install windows 7. Six months ago i decided to fully switch to w10, but my mouse wasn't the same. The mouse lag was ridiculously bad, especially in games. My sensitivity felt slower and my mouse was not precise and fast when flicking. It was like dragging my crosshair into mud. How did i fix it? I went back to windows 7. I didn't try a previous version of windows 10 because I am done beta testing bad software. Looks like I was right since you didn't fix anything installing the Anniversary Update. I disabled game mode/game bar, I checked the "disable fullscreen optimization" in every .exe etc. everything I did was useless.
I know you have an 8700k, but there should be a way to patch w7 so you can try if the problem still persists.