Cabell,
As you know, I, like David Gookin and Ran Morrisett, am a huge fan of the the Cascades Course, the Homestead Resort and the Old Course.
I have to admit that I've not played the Lower Cascades so I cannot comment. I've only been there with my family and I couldn't play all the golf I wanted to so I stick to the Flynn courses. Since I only get to play 3 times on those trips, I play twice on the Cascades and once on the Old.
As for families, there's all sorts of outdoor recreational activities including swimming, mountain biking, canoeing/kayaking, fly fishing, horseback riding, falconry, etc. The kids love it and the wife loves the spa. We've been there in the summer and early fall and think it is awesome.
We haven't been to the Greenbrier. I guess I should take a trip over there to play some golf when we go again. I have been told that the accomodations are nicer at the Greenbrier.