I honestly always have thought we needed an earth science forum. I'd break "Ecology and Environment" and "Evolution etc" and reshuffle the relevant threads into it, and then combine "Evolution" with "Ecology" and the rest of "Environment" with "Politics." That is if this were my forum. But of course, I don't have a life and could probably sit around and actually go through re-arranging threads. It's kind of hard to change a forum once its settled, isn't it? You'd have to go around sticking threads different places or make archives or some such hassle.
I'd be for a social science forum, perhaps with anthropology-sociology and psychology subsections, but I wonder if there would be much traffic. Psychology already has a forum, and I've seen a handful of sociology-themed posts, but I have a feeling people wouldn't realize that they're posting something sociological and just put new threads somewhere else. There have been even fewer cultural anthropology threads, and physical is already covered by "Evolution."