I'd suggest much heavier modding of grown-up debates in the GD forum; and a new, 'name-calling' forum for the five or six who just want to be silly to each other. Open yer trap- clank! Starve em of bandwidth.
Or perhaps only give entry to the GD to those that make regular posts in other sections - it is after all primarily a DIY site and not a political forum. Why people join up to a diy site and go on to make less than a hundred of their 11 thousand posts diy related baffles me.