The problem is, unanswered questions are not necessarily good code. Either nobody bothered to write an answer or nobody had something to say about it so far.
Upvoted, unanswered questions can stand on their own as upvoted, unanswered questions. They are good questions, but no one knew an answer to it. There's no problem with these and I don't think there needs to be a mechanism to handle them. In this case (CR) I think that these questions stand for "hey, that's interesting code, it's well written and I have no idea what you could improve", there's no problem there. Some day somebody might come along and see something.
Not upvoted (zero-score), unanswered questions on the other hand need to be investigated, because there's something wrong with them. No upvotes and no answers can only mean one of two things: Nobody looked at them or they're not good questions.
I don't see the need for an extra feature to handle these types of questions. The good ones stand on their own, the bad ones already get reviewed.