I think what you see on Fluther is about as good as it gets on the internet. The frictions here are just what happens when you allow divers people to express themselves in an anonymous environment. So unless something happens to change human nature, this is what it looks like.
The modding helps a little. We weed out those who just want to stir up trouble, we break up the worst of the fights and we mop up the pages afterwards, but there’s a limit to how far we can carry that. Conflict is normal—healthy even—so if Fluther is to be an honest representation of our community then room has to be made for some rough and tumble. At what point is it “out of hand” and toxic? When feelings are hurt? When someone takes offense? That would mean that a flag on a comment would be automatic grounds for removal. The most sensitive people would end up being the arbiters of content. But at some point, we have to declare that things have gone too far and step in. Until someone comes up with an algorithm for identifying exactly where that point lies, then we’ll just have to defer to the judgment of level-headed human beings (understanding that not everyone will be happy with the outcome).
The General and Social sections have some role to play in this, too. If you post a Q in General, it should be with the understanding that you’re limiting the range of responses you’ll get. That’s a choice. In return, you get answers that bear directly on the question, and won’t stray into peripheral matters. That’s not a recipe for fun, admittedly, but it’s a good way to get useful information. If you post in Social, then it should be with the understanding that even comments that you personally find outlandish or offensive may get to stay. With that kind of freedom, both fun and bruising are possible. Welcome to the human race.