I think that the promotion % should be raised a lot. I like 8-15%.
I also think that there should be a lower % for really new members (maybe less than a month or two old). Maybe keep it at 4%-5% for them?
I honestly think the percent that is taken in promotions should go down the more surveys and things that you do or the longer you're a member the less percent you pay in promotions. Gives an intensive to do more surveys and be a member longer. Maybe?