I think one of the nuances will be the definition of a family. Not who is in the family, but I would expect only 1 person can be the head of the family and add people to that. I create a family, add my kids, sister, brothers, close personal friends, etc. I don't think then my kids can add people to their family.
I think everyone will be able to setup their own "family".
But just because I give you access to my game, doesn't mean by extension, I've given someone you've defined as a family member access to my game.
It isn't a daisy chain.
Parental controls may permit the parent to limit who can create or access a family, so maybe you don't let your youngest setup a family, but your eldest can. As it exists with the friends list. Parents can define whether or not child account can add friends.
If that is the case then it is an even better feature. I would be thrilled to have it the way I defined it and ecstatic the way you described it.
Well, there is no family plan. So, there is no "master" account to a console. So everything you setup or own, you take with you. I think they chose "Family" instead of "Clan", which had been appearing in several patents.
I kind of like Clan since it's more Scottish, but Family works too. A member of a clan can be anyone, but most definitely a family member including extended family, a member of your family is a member of your family.