In other words: Moderators who enforce the spirit of HN and have the ability to just kill stuff. I'm really surprised this isn't happening already. If I go post some derogatory remark on a heavily moderated blog or forum, it's get's junked almost immediately.
The old weights were ok for the more engaged users we had a year ago, but now the ratio of votes to flags on a fluff story tends to be a lot higher.
Giving flags more weight is not necessarily the answer. Punishing people for making bad comments is, I think, more important. Equally important is punishing people for upvoting bad comments.
But now it's late here, and starting tomorrow I'm really not going to be here for a while. Good luck PG, I hope you can find a way to reduce the mean-spiritedness fluff, and make HN more pleasant again.
I think this last sentence is very telling. Low quality is only part of the problem. What really makes people want to disengage is having their feelings hurt.