Robert
As you pointed out, one of the reasons the ball is travelling so far is the increased clubhead speed. And one of the reasons they are generating more speed is the increased strength and conditioning of the modern golfer, there has been a great emphasis on becoming more fit. You combine that strength with improved shafts, lighter stronger materials, larger heads and much larger sweet spots and balls that resist curving, and you have the modern dilemma. Even the less fit seniors benefit from all these factors. The forgiveness of modern equipment has has increased the importance of strength and the ability to generate speed.
You can attempt to decrease the distance of the ball, but all distance measurements are relative to certain clubhead speed. You can turn back the ball by X%, but if clubhead speeds increase due to other equipment advancements, what good will turning the ball back do?
Not only does the distance the ball travels need to be addressed -- but also the size of clubs, the materials used for balls and clubs and the effects of dimple patterns.
The USGA and R&A needs to produce a standard ball -- made of a standard material both for the cover and the interior, with a standard dimple pattern -- no derivations. The other sports play with a standard ball, including materials and seams, why not golf.
They also need to standarize the size of clubheads, just as they limit the size and shape of grips. No oversized heads and I'd seriously consider forcing woods be made of wood, just as baseball requires wooden bats. Shaft materials also need to addressed.
If you stop innovation dead in its tracts players will need to look to other areas for improved results -- especially skill. Golf is a sport where it is man against course, man has been gaining dramatic advantages over the last few years and unfortunately the golf course has been forced follow suit -- the result has been detremental to the game. Wouldn't it be nice to put an end to it all -- the new refrain would be "we need to shorten our course".