I'm a huge fan of Donald Ross courses, esp the early ones done before a lot of the earth moving equipment and drainage equipment was available.
However I do fear that the old courses are quickly becoming obsolete with the longer drivers and balls that make a 300 yard drive a short shot. Pinehurst #2 is the gem of all the DR courses and I applaud them taking it back to how it was 75 years ago, making the sand bunkers and areas more in play which should lead to a great US Open for the men and women in a few years.
However Pinehurst #2 like many of the older great courses can only be lengthened so far and it is close to that now. You can make one of the par 5's into a par 4 and push the tees back as far as possible but you only have so much room to work with. I felt that the PGA at Whistling Straits was a good example of a course that had no real history or tradition but was given the PGA and a US Open soon I think just because they could make it long and difficult. Maybe it is time to think about a restricted ball for the PGA much like the softball players went to several years ago.