I agree with those above that you really have an eye for this and I enjoyed these so much! I especially like the mythology comparisons, like Stephanie/Eric as Hera/Zeus is spot on. For Steffy I would say the "Cool girl" archetype has at least been part of her characterization. Admittedly, I have not seen a lot of the more recent years.
I also agree with when you bring up Brooke that it changes over the years, and I think one of the reasons is that soap characters are often characterized as oppositions to each other (I can expand on this later, my seminar is starting soon, haha). So, Brooke's characterization has shifted depended on who she's in a storyline with, as has most characters. I think one catalyst for Brooke in particular was the departure of Stephanie, which kind of messed with the balance of her function as a character (and the show as a whole).