From what I've read in this thread, it seems to me that you would like to encourage more members to actually post. I don't know if removing access privileges to the entire site will accomplish that. It really depends what you want the site to become - either a small group of active members or a larger group which will consist of lurkers, etc. who are into the site but don't feel compelled to speak. From my experience, usually people tend to lurk at a sight for a while before they begin to post so if you're are too hard core about requiring posts, you will inevitably negatively affect the amount of people who will eventually become members. It doesn't hurt anyone if some members don't post but I do understand your goal of promoting more active membership.
Other sites ie Ninjashoes.net have similar polices but they only limit access to certain areas like the video/media section until you have a certain number of posts. That way people can still lurk but there is an incentive for them to become more active.