JC,
I am not sure if this is what you were going for, but the first consideration (in my opinion) on LOng Island, is the invite. I would love to join Garden City, or Shinnecock, but i check my mail every day and so far no luck!
After the invite, the second phase for younger people becomes the pure economics. I am a member of a golf only club that closes for the winter and therefore the bills stop for several months. A good friend of mine, is the same age, accepted an invitation to join a "Country Club" which has an arguably better course than mine, a pool, paddle tennis, squash, a year round club house, year round minimums and year round bills. He has no kids and doesn't play tennis. He is often left wondering if he made the right deicsion with his club. With the economy the way it is, I think people would rather join a club that only has what they want i.e. golf, putting green, and bar.
To be fair to both of us, I got lucky that the only place that would have me was a Golf CLub, and at the time he joined, the Country CLub was the only prospect on my friend's horizon as well.