I repeat this a lot, but I think the most important thing to do is to stay sincere and not be a defeatist. No arguing just to win, but no hugbox mentality either.
I have no doubt at all that the reddit admins and powermods were algorithmically pushing flame bait and hatred (especially to the political subs) to drive traffic to the site, so now that we've have a place where that isn't possible (yet, at least), I'm interested to see if that's just the nature of political discussion on the Internet.