I have never used vBulletin before, but am fairly well versed in phpBB. In that format, there are options for almost everything, however you have to be the main Admin to do any of it. There are options for limits on users based on post count (essentially automated movement of group and permissions based on post count)... As well as a myriad of other options. I have recently set up such a system on a website that I co-developed for my online game that I play (yes, I am a World of Warcraft nerd, dont judge me). The forums were actually a small part of the site, however for setup and permissions, security, etc, it is the largest part of the ACP.