A few suggestions...
I like the idea of having a forum just for venting - it may minimize the antagonizing replies people get if that forum is specified.
I also like the idea of having a forum for the good stuff.
BM/BD issues section, marriage issues section, maybe a few off-topic sections to give this place more of a community feel - off-topic, TV/Movies, etc.
And, of course, assuming y'all read my post in the site suggestions forum, have differing levels of security depending on the topic. I know for myself, I feel a little anxious posting sometimes in case someone I know stumbles across this site.