The old adage "to each their own" applies to many things, including peoples' opinions. So, as entitled as you are to yours, and I respect that, in order to see the true value of Amazon, you need to stop weighing just the commission percentage.
When you factor in the MASSIVE database of products and product categories multiplied by the fact that you earn commissions on almost EVERYTHING your referral purchases, the lower commission rate is definitely out-weighed, IMO anyway.
Don't get me wrong, I used to be of the same mindset, I wanted the BIGGER commission percentages, however, I hardly EVER receive a check from Amazon that isn't at
least 4 figures... a lot more than I can say for MANY of the other products I promote which carry a much higher percentage.
In the case of Amazon, the sheer quantity of "everyday items" as well as "far fetched items" definitely wins out - bar none. Again, IMO of course.
Furthermore, I agree completely with your "i am opposed to dedicate my site for a single network / or affiliate program" statement. No one should EVER put ALL their eggs in one basket, be it online or off...