Rules and Regulations
I know I have visited communities where their rules, guidelines, terms, etc. are longer than most of their topics. I really do not like that approach as it's not very welcoming and, really, honestly at the end of the day no one reads or cares about the rules. People know what is proper and improper behavior and do not need to be told not to use profanity, make personal attacks, post in the wrong areas, etc. - written rules or not people will still be people and do that.
Take the rules here on the IPS Community:
If your post content, signatures, profile images, etc. are disruptive and impact our clients' enjoyment of our community we may ask you to refrain from such actions or revoke your access to this community.
I think that gets the point across. Don't be a disruption and you're good!
Way too many forums and sections
This is mostly true for new communities. You're starting a new community and are understandably excited so you create many categories, forums, and sub-forums. So many in fact that your home page scrolls and new members have no idea where to post. Not to mention the fact that your site looks like a ghost town with topics scattered about dozens of forums.
Having many sections makes sense once your community is established and you need organization to keep things easy to read. But when you are first starting try not to overwhelm your visitors with too many areas.
Does your News forum really need a description that says "This is where we post news and information about updates to our site. I hope you read it and comment often as it's very important. Read this first!" ... I mean the title "News" kind of says all the same in one word. There's nothing wrong with description when needed but just because IP.Board has a "Forum Description" box there when creating a new forum does not mean you have to fill it out.
Ask yourself if a forum you're creating needs a ton of explanation perhaps it's not needed. And surely not every single forum needs description text - it just starts to clutter things up and creates a lot of scrolling to see the list of forums.