I don't see any percentage in formally establishing a Family.
For example.in my neck of the woods (Western PA ), there is virtually no Mob presence left.
If a couple guys can put together a strong crew,take care of the Cops and Politicians,and not leave bodies in the street,there's always money to be made.
Why subject yourself to all of the aggravation that Millspgh mentioned ?
Keep a low profile,do your business,and live long enough to bounce your Grandchildren on your knee.