Actually owning an IM, IMO there is always room to increase and seperate circuits for easier trouble shooting as time goes on. So feel free to seperate some and add a few. Better now than later. H4 headlights for example. etc .
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .