Tying up Yunlan lightly? Yunlan's blood circulation might be cut off and he might lose the hand, Shen Wei could never do that!!!

I agree - anything with the slightest chance to hurt Yunlan would be very difficult to persuade him to do ( luckily Yunlan can be very persuasive)

the hard task of trying to dig out all of Shen Wei's kinks

So much this. Your headcanon is my headcanon and I wish someone would write pillow princess Shen Wei (plus the arduous lead up to that state).