Upload & Sell: Off
Pros don't really want to give away what they know...
Seriously? I think you are off on this one. I have found many people in the forums to be helpful. Today I enjoy taking portraits and it is all because of so many people willing to share as much as they do.
I bought my first slr camera in 1980 and struggled for years to figure out how to take a portait picture I would be proud of. Eventually I gave up and quit shooting for years. Seven years ago I bought my first dSLR and found the world of forums and professionals willing to share their knowlege freely. Behind the scene shots, lighting diagrams, equipment lists, etc. I have even found pictures I liked in online galleries and sent e-mails asking questions and to date every one has been answered. Most people share what they are comfortable sharing and that is fine with me. Lisa for example doesn't share her post processing recipes, but she does share her before and afters from time to time which to me is even more valuable. I truly enjoy seeing her pull back shots when she shares those!
Back to the OP... I think you have a great idea and there was another forum that I used to visit that did exactly what you suggested (I think the forum was part of a company that sold backgrounds?). They had threads for 1 light, 2 lights, 3 lights, 1 light with grid, broad lighting, short lighting, etc. The thread starter would post a lighting diagram along with a sample picture and then others would post their attempts. The critiques were somewhat subjective, but at least people were trying different things....
Hope it works out..... I know I will learn something.