Here are some suggestions that I got from our active user base.
1) The ability to be able to choose either PM or Email for message replies.
2) A rating system for posts. Users can rate posts (for instance, 1-5 stars).
3) Something to help keep too many reposts of the same or similar topics. i.e. When a user is making a post, if there were a check box for "Check for similar post". On submit, the forum would display a list of posts that had a certain percentage match and the user could see if it was a repost.
MySavings