I feel like the only reason we're not seeing more of him is because of the goal threat Gundo had in comparison. It feels like it should be a straight swap where Kovacic replaces Gundogan in what we played last season. Eddie, Walker/Akanji, Stones, Dias, Ake, Rodri, Kova, Bernie, De Bruyne, Foden, Haaland.
But the system was Stones-Rodri with a front four of Bernie-Gundo-De Bruyne-Grealish behind Haaland. Kovacic doesn't work in that role and Pep clearly doesn't want to push Rodri too far forwards too often because of his control of the game.
I think the main issue we have is the discipline with Grealish on the left, which we don't have if anyone else plays there. Foden's more inclined to get into goal scoring positions. De Bruyne likes playing the inside right channel and if we lose the ball it's often leaving us exposed on the left hand side - not the case when Grealish holds his position.
Grealish could just be the key to this season...