I honestly typed in Bettenhausen three times and opted for someone else.
I also don't know how good Dickson and some others were in their time. Just because they didn't win a lot, doesn't mean they weren't always in the hunt. Harder than it seems
Clauson IMHO is right there with Vogler. If you beat him, You've accomplished a major feat.
No doubt Shatz is dominant in Winged Sprints. About the only reason he didn't make my list is because most of the ones I listed were good or great in many kinds of cars in many forms. Winged and Non, Pavement and dirt. Nascar and Indy? 24hrs daytona etc. But go up against Shatz at any dirt track in a Winged 410. Good luck beating him.