Blocking links to paywalled articles might help, although I'm sure people will disagree with that idea (you can detect most paywalls, as they try to play friendly with Google).
You might try to find a way to soften the influence of people who are badly behaved voters, and causing those comments to float to the top. A lot of review sites seem to suffer from the people who give well thought out ratings being drowned out by a majority who only ever give the minimum and maximum rating. That's made some sites give up and only offer thumbs up and thumbs down, but if you can detect those users, you can always try to reduce the influence they have on the final rating.
You might try to find a way to soften the influence of people who are badly behaved voters, and causing those comments to float to the top. A lot of review sites seem to suffer from the people who give well thought out ratings being drowned out by a majority who only ever give the minimum and maximum rating. That's made some sites give up and only offer thumbs up and thumbs down, but if you can detect those users, you can always try to reduce the influence they have on the final rating.