The recent implementation of a -5 karma penalty for replying to comments that are at -3 or below has clearly met with some disagreement and controversy. See http://lesswrong.com/r/discussion/lw/eb9/meta_karma_for_last_30_days/7aon . However, at the same time, it seems that Eliezer's observation that trolling and related problems have over time gotten worse here may be correct. It may be that this an inevitable consequence of growth, but it may be that it can be handled or reduced with some solution or set of solutions. I'm starting this discussion thread for people to propose possible solutions. To minimize anchoring bias and related problems, I'm not going to include my ideas in this header but in a comment below. People should think about the problem before reading proposed solutions (again to minimize anchoring issues).
Alternately: a (very low) karma requirement for comments and posts to the discussion subreddit (~20?), a somewhat higher karma requirement for comments and posts to Main (~200?), and a newbie subreddit for new posters to post in. Regular newbie forum topics would be welcome threads and stupid question threads; anybody could post in the newbie forum, so there would responses from LW veterans, and anybody would still be able to ask Stupid Questions. (Meetup threads possibly should go there too.) (Depending on how many other topics there are, it might be worthwhile for every introduction, meetup, and question to get its own thread there.)