Thief’s difficulty system should definitely inspire K:CDs if there is any form of difficulty system. Turning off HUD elements like arrows and stuff you shouldn’t have is great. But IMHO you should still have some form of marker so you don’t completely forget where you’re going - but it should be quite rough/general. I found Dishonored’s arrows to be really interesting - you always knew where your target was but you were left totally to your own devices to kill them. Also with the lieutenant: If you caused some form of alarm (IE hitting the ground with your sword) and then you disappeared, Campbell would run to his room and the lieutenant would just run away. That’s how I always did it.
I really felt Skyrim was an actually awful game after playing it for so long. The lack of depth and terrible combat ruined the replayability, yet to this day I can easily start another character of Oblivion and have fun. The dumbing down actually led to the game’s difficulty becoming something you could just game because you knew it worked. (Don’t have difficulty sliders that affect damage done and damage taken!!! Can’t stress this enough). Most of the animation cycles for weapons became too long because two Daedric swords one hit anything. Even with very extensive modding I found these issues were only ever lightly alleviated. This is something I cannot foresee happening in KCD, which makes me very happy.