Like I said, though, there isn't as strong a dichotomy between users and editors as you seem to think, and you seem to want to encourage there to be one.
I neither presume nor advocate a clear distinction between users and editors. I'm not sure why you think I would.
I do, however, recognize the fact that editors will likely have some baseline understanding of game concepts, including the concept of quality. If someone doesn't understand what quality means in DF I doubt they'd try to edit articles.
I largely agree with your statement regarding the desirability of turning users into editors, but I think it's more accurate to say that the purpose of the wiki is (1) to educate and inform new players of game mechanics and concepts, and (2) to consolidate game information from the forums and other sources for the use of all DF players. Obviously, I think the primary purpose of the wiki is to serve new players.
The question, then, is how do we do that? Questions regarding what form the quality labels should take should always start by asking what role they serve in furthering the greater purposes of the wiki. I believe that quality labels have little direct relevance for new players and primarily (not exclusively, but primarily) serve the second purpose.
You say we need to warn new players about unreliable/incomplete information on the wiki. I think the other mechanisms we have in place (D for Dwarf, disclaimer on the front page, discussion pages) sufficiently address this concern. I also think the quality of the articles is self evident, even for new players. I refer you to the examples in my prior post.
The only way I see quality labels being directly relevant to a new player, so new that they aren't familiar with DF's quality hierarchy, is if they see it, say "I wonder what that is", and click on it. Of course, if they do that, they will not only clear up any confusion regarding the article's quality but also have a chance to learn about the game concept "quality".