Your current strategy is to make all your money from selling as many premium, high pay/per/month accounts as possible by loading up that alternative with your best bells and whistles. I suggest you consider the Gillette strategy - "give away the razor and sell the blades" currently being used by printer manufacturers - "cheap printers and very expensive ink cartridges". Put your premium features on your pay-per-response plan and raise the fee per response so that you have more users with smaller audiences. In other words - tap the huge web population of smaller users rather than focusing on fewer large users. The big money is in the volume of responders potential of the web.
Thank you for sharing your thoughts. We designed our Pay-As-You-Go plan with low-use, cost-conscious users in mind. Its feature set is quite comprehensive, although I realize that it isn't necessarily the right feature set for everybody. What feature do you need that isn't available in this plan?