How large are your builds? 4GB of RAM is $40. Building off a RAM disk is going to be quite a bit faster than an SSD, for 1/10 the cost and much less evident risk.

Ahh, trolls? Usually these people have a point, but are ineffective at communicating it, so their style becomes aggressive. Your measures are punitive. Here's a novel idea for many communities: try to understand, help and enable trolls. They probably do have something to say, which may not be the mainstream view but is still valid. You may not be ultimately successful, but your community will grow stronger and mature beyond grade school behavior. As the Internet expands communities where people are treated as equally and honestly as possible will become more normal. Think of wikis where typically 'users' have about as much control as 'admins' to create and edit pages, categories, etc, or twitter where celebrities can talk in a more normal, less managed fashion. There are already too many communities (typically forum based) populated with corporate apologists who take pleasure in shutting people down over ultimately reasonable or progressive issues. These communities become more fixed and exclusive and like an aging population, become smaller and die off. If you just want to do it for your job it's one thing, but to build an honest participatory future it's better to shoot for the horizon.