The thing with Ceiling is that one can raise their ceiling by control. Look at Glavine and even Maddux for example. Maddux had good stuff but his control was what made him the best... Glavine is the same. He had a devastating change up.. but he knew how to paint the outside corner and just will the hitter to swinging at his pitch. Neither guy had 'stuff' that just blew you away.. they just had superb control and smarts. So a guy like Blair/Wisler/Gant who just know how to pitch and get guys out could just as easily become 'elite' as a guy with great 'stuff'...
I know in the context of the OP.. we are basing this on 'stuff'.. because imagine a guy with Maddux control and Touki stuff... WOW!!!
This is the main reason I'm so high on Blair - I spent so many nights watching the Big Three 20+ years ago and honestly still can't tell you which one was truly the best Pitcher..