Cynthia,
When I first saw this thread on Sunday, I clicked on the $30 category in the poll. At the time there were hardly any responses, so I picked an amount that is half of what local artists organizations charge for annual membership (and for which they deliver a lot less value than this forum).
My only misgiving about instituting a fee for membership is that, inevitably, it will mean that some members will discontinue their memberships. I've grown very fond of all of the members, and look forward to seeing their posts, especially of their work. There's not a single person on this forum that I don't think of as a friend, even if that sentiment is not always reciprocated.
As far as the way in which you've conducted the forum is concerned, I think it's excellent as it stands. If a fee is necessary to continue your good work, then you and the moderators, etc., are entitled to be compensated. Money is one form of compensation, but for your overall effort only one response is adequate: SUSTAINED APPLAUSE!!
John