The problem with a lot of forums for me is that it's like a lot of television channels, no one of them gets very many watchers. If one has an hour, for example, and there are four forums, then one can read and work for 15 minutes per forum. But that same hour over 15 forums only goes 4 minutes a forum.
I realize that one doesn't have to read every forum but adding forums adds complexity to everyone and where I had only 4 to begin with, I'm still going to "channel surf" 15 to make sure I don't miss anything "good" and since the lines aren't perfect between forums, someone is going to mention that over in forum X such and such is happening and I think people will feel left out because they don't normally read forum X and maybe even resentful because forum X is mentioned in forum Y. Like now, how about bi-sexual guys? Here we are in the women-focused support forum and they may not read this forum and/or people who don't read either of the gender forums won't have a clue that people are talking about adding a forum. It gets much harder to know where to post when things get so divided up.