sounds like you created a whole list of nitpicks. I personally love Big Sur (come on, you are really upset by an icon?)
If it was a single icon, or even a collection of icons, I wouldn’t have a problem. The issue is the entire interface. As I specifically mentioned, there is an extreme lack of contrast b/w foreground and background windows. That’s a big problem when you have multiple windows open, and can’t easily tell which is the active window.
I’m glad you’re liking Big Sur, but to say my “complaints“ (which they’re not, they’re legitimate usability issues) are just a collection of nit picks shows that either you didn’t fully read my post, or you really haven’t dug that deep into the OS.