I think for Pine Valley, you have to look at the club first. It had a completely unique model as it is my understanding that it was really established as a "winter club" mainly for Philadelphia golfers who did not have the sand base on the Main Line that Pine Valley in the Pine Barrens of New Jersey had. It may be near the Mason Dixon line, but if you are thinking of playing golf locally in Philly during January, you are a hard core golfer.
National, Shinnecock, Fishers, Misquamicut and Atlantic City were all seasonal clubs where people vacationed. Maybe Atlantic City was year roundish, but it was a club for family trips to The Shore. I am guessing that Myopia and Essex County were similar "country/seasonal" courses but I don't know the North Shore of Boston that well and I have not been to either.
Augusta, Seminole, Pinehurst, Mountain Lake and others in the Florida were all winter clubs that you traveled to.
I would argue that Pine Valley was the first "destination" club now made popular by Sand Hills, with cabins and rooms for the hard core golfer who wanted to play year round without going South. No planes involved, but Clementon, NJ is no vacation spot and in the 1920's it was probably not that easy to get to from Main Line Philly. I would imagine that everyone at Pine Valley was a hard core golfer.
Tom, I would be interested to hear more about the early membership. It is my guess that the entire place was and still is driven by golfers, who goodness forbid in the 1920's, actually had to work for a living and did not "winter" down South.
From my limited experience at PV, it is my impression that the place is all about golf. The staff, caddies, members and guest all seem to keep the focus on the golf. I have heard that Augusta has a similar atmosphere but I have not seen it first hand.
This all sets up for the Muccish Benevolent Dictator to run the place and prior to that a Benevolent Developer in George Crump who can set up an All Star collaborative architectural team that then produces the great Pine Valley on a sand based and rolling playing field.
Will Old MacDonald with its collaborative team be the modern Pine Valley? When choosing schools and golf courses, I always prefer not-for-profit over profit, but that is not to say that Old MacDonald will not have a unique atmosphere.