I am quite proud to serve as a member of America's senior service. BTW, Soldiers are not in the Army; we are the Army.
You need to read less David Hackworth and more books. BTW, he is a friend of mine and I am a friend of his. I have met him and we correspond fairly regularly. So hold off before you resort to lumping me in with the perfumed princes.
You are correct in that Parachute wings do not automatically a leader make. Neither does the Ranger tab. But I seem to know a lot of Marines who went, graduated or want to attend that course. It is an indicator. Gen. Pace probably went as a Midshipman or as a young 2nd Lt. So for his 3-weeks at Fort Benning, Georgia, 30 plus years ago, you deem him less than optimal for the position of Chairman? Your problem is not with him, it is with HQMC and Uniform Branch.
Next, you are refering to a distinguished group of officers from a day when virtually no one had civilian graduate degrees. They went to military schools, often for years and taught though. Their equivalent education was easily Masters level if not Doctoral. Patton had a personal library that would rival almost any high schools. There was even a book written about his books and reading habits. Eisenhower, a middling student at West Point, graduated first in his class at Command and General Staff School and from there his career took off.
Westmoreland was a terrible strategic leader, but he was quite a superb tactical leader if you actually go into the record (he commanded the 187th ARCT in Korea). He could not transition to the mindset required. But I can easily cite Ridgway, Taylor and Gavin to counter Westy.
As for Grant, he spent the pre-Civil War years pickling his liver as a failed businessman, not commanding troops. Now McClellan on the other hand had a quite extensive troop command resume.
I assume you meant A.A. Vandergrift, and not Vandergriff (the surname of a a less well-known, but still distinguished and well-published soldier and close friend of mine).