well good to see they got this going

I agree that the buyer referral program is very generous and the best of any site.
the statistics and their layout and the plethora of links that you provide are also very nice.
the photographer referral program however, is not on par with the other sites. Any new photographer doesn't have much of a chance to get images online and start getting sales within the first 6 months. By the time they actually have a producing portfolio the referral time is over.
Dreamstime had 6 months referral time for photographers and they changed it to 3 years. They give 10% as well
shutterstock gives 10% (or a little more depending on the level of the photographer) for unlimited time. (this is the best referral program of anyone)
Fotolia gives 10% of the photographer earnings for 5 years (second best referral program)
I hope you can reconsider the length of time the photographer is counted as a referral.