Just wondering why the board is configured not to show any avatars in the post displays? I haven't seen anyone else asking this question and there is no mention of it by the admins anywhere (correct me if I am wrong).... A little bit of playfulness would do unix.com good 
Will consider your question to give it the thought and consideration it deserves. I've seen lots of board with Avatars and they don't add to the quality of the board and require additional administrative overhead.
However, I'm too busy with my 'paying jobs' to give this the due consideration your question deserves. More later.....
I think the overhead is minimal if you disallow custom avatars uploads. On my own board (http://www.baanboard.com) I have uploaded +-500 small cartoon characters and that's what I stick to. I also miss the ability to add sigs the posting sometimes.