Here's a thought I had while driving to work. Yes I do think sometimes.
What would you prefer, a sponsor who does everything he possibly can for you and pays 60% or one who does little and pays 70%?
The % may change due to differing programs, conversion will stay the same as it's the same program.
What I'm saying is, nothing is for free in this world. The tools cost money, money that comes from the sign ups the affiliates send. So would you prefer little support, maybe just the content and a bigger slice or all the tools and pay for them with a smaller slice?
I think 10% would cover it and attract the better affiliates. Think of the cost, hosting, banners, galleries, STAFF, etc. Then think "I can do this for myself, do it different and earn more money or I can take all the tools and save time to drive traffic. Which is best for YOU?.