I was in the process of answering a question and had to convert it to a clump of poorly formatted comments when it got moderated. The specific question was a relatively typical off-topic one, essentially: "How should I 2D?" It got me thinking, though..
Rather than moderating 1,000 duplicate questions per month, allow the (meta/moderator) community to vote/decide on a very small handful of "off-topic" questions to give good, solid, "best way" answers to. The purpose of the questions and answers could still be aligned to the site's principles by giving them a minimal starting point and/or diverting their question AWAY from this site.
Questions like "What is the basic outline for a 2D game?"
This could be opened, a minimally-comprehensive, single, (meta/moderator/community) answer generated, and immediately closed with no further answers or comments; a "sticky" so-to-speak. Anyone searching for approximately that, would get some basic highlights of what to Google (and not StackExchange) next. The "community" answer for these few questions could just be external links to wiki or book titles in quotes. Duplicates that get posted anyway could be linked to the sticky which would, again, divert them away from here until they have better questions.
Just an idea...