I've been in a lot of houses through community nursing and pastoral visiting. Nursing you see people as they are, usually things are a bit chaotic with a sick person in the midst.
What I've generally observed is that no matter how big the house. People live, congregate in the one designated family type room. They may have multiple living areas but one area is used where everyone hangs out. (It also occours to me in some houses which are gigantic and only one or two people live inside that there is an absolute waste of space!)
What I've also observed is that where people don't have a communal space there is major dysfunction.
On a pastoral home visit once I noted that a normal three bedroom house was totally invisibly divided between the adult male and female. While their children blurred the boarders. There had been a marriage separation under the same roof. There was not the one room where communal living occurred.
What I wonder is, can you design a home which improves family life? Or a great family life will always make any residence feel like a home? I suspect the answer is a bit of former a lot of the latter.