I think Zhao Yunlan has the "I am schmoozing with people because a Chief has gotta do what a Chief has gotta do" smile, and he also has a genuine smile for the people he cares about, like when he's snuggling with Da Qing on the couch, or when he sees Shen Wei for the first time after his eyes are cured.

The first bit of cat-and-mouse games he had with Shen Wei definitely had a quality of him wanting to trust Shen Wei, and being drawn to Shen Wei in a way he's never felt before. But also still maintaining his suspicion - I call his approach back then flirt-terrogations :P. I think they never truly get past that until the time travel occurs, and by then things have gone to hell too much for them to communicate. On some levels, I wish the bench relaxation scene had happened after the time travel!

I love what you said about Shen Wei wearing a mask and not revealing all of himself, but whole-heartedly loving Zhao Yunlan without any doubt.