This is really interesting. I have thought of watching youtube courses about UI design since It compliments perfectly my two areas of interest which are copy and programming. I'll definitely give It a try after this.
I remember a trick I've learned from a copywriter I follow. It states that to keep the prospect's attention, you should change colors every now and then to keep novelty (As long as they are still the colors of the brand). I guess this would work more on landing pages or those where heavy amounts of text are introduced.
That being said, this is a great post. I would love to know about your experience with web programming/design. What languages do you use for the backend? I'm learning how to create functional websites through Flask for Python and MySQL databases.
RE: UI/UX Colour Rules.