[weaksauce]

you could have a feature on the front page that takes 3 stories from the new feed an displays them at the bottom of the front page for users that are above some "wisdom karma threshold" similar to the downvote threshold. if you want to provide some checks and balances to the 3 stories you could include one that is flagkilled but is not distinguished as such to the user and see what the user does with that story.

You can also have stories with more text behind them as an indicator of quality. While long stories could be gamed, I think it's a decently helpful metric of quality as most spammers are lazy enough not to write a long article. not a perfect metric but something to consider.