Mike,
I always wondered why I liked Raynor courses since playing my first - ShoreAcres - in about 1979. Most of it was the feeling that you were playing a museum piece where "they just don't make them that way anymore." Of course, the SA site was spectacular, too, with the ravines, even if you don't see the lake while playing.
I also think there is something of a lack of self consciousness that is appealing, knowing how hard most of us work to make a very unnatural item (i.e., golf tees, greens, and bunkers) "natural." In other words, they ain't, so let's just put the minimum of work into building them (steepest slopes, simplest shapes, etc.) and not worry about naturalism.
I had a college professor once who was writing a book on things like railroad coaling towers and grain elevators in the prairie landscape. As tall structures on the wide prairie, they do stand out, and have no ornamentation to gussy them up, and in so doing, their very practicality kind of makes them work visually. At least, we appreciate that a grain elevator has but one function and accept it for what it is, even if it is far from natural. Yet, it has become iconic part of the American Prairie landscape for other connotations. In reality, aren't golf courses single function bits of landscape architecture that could have the same qualities apply?
That is a little deep, I guess, but in reality, building something that just is what it is may be more natural and minimalistic in the end than trying to build something that is artificially trying to mimic nature. And maybe, somewhere deep down, we appreciate that honesty in design?