I completely agree with David Gerard on the scaling issue. You can say "there are far too many policy wonks on the English Wikipedia" all you like; just how does that make them go away?
How about saying "there can only be X policies on the Wikipedia, where X = the number we currently have. If you want to add another one, you must first remove an existing policy, by consensus." I.e. keep them constrained within a busy loop, fighting each other's policies. For bonus points, as time progresses, you could try gradually reducing X (using a Last-In-First-Out approach), thus forcing people to condense the rules into "meta-policies" (such as "assume good faith"), rather than obsessing about petty details. And when the rules fit on the back of a Wikipedia membership card in 14-point font, then it's time to stop reducing X. :-)
All the best, Nick.