I'm probably going to be unpopular saying this, but I hate "friends' groups" and the like. If you have a lot, you have special bragging rights that hurts those don't. If you don't have many, your feelings get hurt. Worse, if someone asks to be your friend that you really don't want as a friend or don't know well enough to feel comfortable calling a friend, you either have to say yes even though you don't want to or say no and risk hurting them.
I think I'll just have the policy that I'll accept any that ask, never ask anyone to be a friend and, those who are my friends already know they are and, hopefully, won't need a special invite from me to know that I truly care deeply about them. Truth be told, I care about each and every person on this Board. Some of you might irritate me or even flat out get me really mad, but I still care what happens to you and yours.
Sorry, I think this is a really, really bad idea.