Honestly, none of that. Create your own "ad network". Basically, figure out the theme of your blog and what kind of people it attracts and then find affiliate programs for that. For example. Let's say your tutorials are for developers. What do developers need? * development tools * hosting * further courses/learning That will yield a pretty good list of affiliates that will convert well such as: * New Relic * Digital…
Please don't tell me your advocating using affiliates in place of an ad network like AdSense. While on the surface it makes sense, and if you're lucky you'll find great affiliate programs, but there's an equally, some would say much dirtier side to affiliate programs. Success is the key to how your relationships go. Get too successful and chances are the company you have an affiliate agreement with will get tired of…
Outside of that, I never reached the volume where I had to worry about the pay outs myself.
But I have worked for companies that HAVE reached a VERY high volume (read: millions in affiliate sales) and they had no problem either, as long as a contract was signed outside of the regular affiliate program to control traffic, cost, etc. I think that's the only reasonable thing you can do: have a direct partnership with another company once the volume reaches a critical mass.
Having an alternative is, of course, a must-have. Or rather, like you said, diversification. Having multiple affiliates, multiple working relationships.
I don't agree with you on direct ad sales. It doesn't mitigate anything. It's the same deal as the rest of the advertising world, nothing special about it.