Per the Rich Eisen show he discussed Tomlin's coaching with TJ Watt and got some semi-clear answers. Essentially it sounds like Tomlin's coaching style is to lead you to improvement, but doesn't hold your hand. He inspires players to improve but treats them like adults. TJ Watt said basically "I love Tomlin's style, but I don't know why it doesn't work on some of our other (younger) players."
It feels like the methods Tomlin uses resonate with "old-school" players or ones that have a deep love of the game/drive to get better, but doesn't engage younger players with different mindsets.
If they keep Tomlin, they have to do what the Pats did (successfully for many years, now not so much) and get players that fit that Steelers mentality that existed ~10+ years ago. Players who feel like Steelers and have a drive to be the best they can be. AB might have been nuts and a diva, but at least he honed his craft incessantly and worked to be the best WR in the NFL. Bell on the other hand did not have that drive to be the best and focus on football.
It feels obvious which players have that drive and mindset that resonates with Tomlin, because those players seem to do the best in our system. When I think of that old school Steelers style the players that fit are those like Watt, Heyward, Minkah, Highsmith, Najee and Warren. It feels like some of the rookies like Broderick Jones, Nick Herbig, Keanu Benton, and Joey Porter Jr also fit that mindset.
Hopefully, even if we get a new coach, the Steelers will continue to find a middle-ground between talent and mindset. I think we did a great job of that in the last draft, but we'll see.
Would not be shocked to see both Pickens and Diontae traded this offseason, but I'd rather keep Pickens and find an OC who can keep him engaged (if that's possible).