1. If you are writing self-admittedly inflammatory material, and you get inflammatory responses, you should try stopping doing that and see what happens before suggesting changes in HN. People are mirrors.

2. You can flag inappropriate comments (click on their link or parent link for the flag link to appear). [EDIT maybe there's a karma threshold to see the flag link.]

I think swearing and meanness is very rare on HN. I would say there is a fair bit of "scrappiness" - argumentativeness/combativeness - which sometimes undermines the productivity of the discussion. But although annoying, it's quite different from mean spiritedness.