I simply cannot imagine doing that anywhere else.
And I doubt that any of my comments rate as insightful or beautiful. Yet stopping me making them would have killed those conversations.
I can agree that the submissions seem less interesting than 5 years ago, but the conversations engage me as much as ever, which is fine - HN has changed - it has become more necessary to participate - it is not wikipedia - its not supposed to be a passive read.I have been a lurker here longer than my username, and in the past year it has been noticeable that HN is more like a conference - the interesting stuff happens talking to people in the corridors.
My 2 cents suggestion - hashtag comment threads. Then the best comments, most insightful, most summarising, can be extracted on any given hashtag subject - a living FAQ if you like.
But don't make huge changes - the real stuff is about talking with other interesting people. Thats great - lets not risk it with big unproven changes.