I don’t mind more Kanter, but what would the style be that better suits them? Al is one of the better (their best?) ball movers and decision makers, so I could see more high post sets through him, but I’m not sure if he can be the straw that stirs the drink through a season.
I was using Kanter as an example, not as the whole story.
If they are playing Kanter, the strategy needs to be drop coverage on pick and rolls.
Ime wants to switch pick and rolls. The offensive center sets a pick for the ballhandler. When the ballhandler uses the pick to shake his defender, Ime wants the center (Al or Rob) to leave the pick-setter and guard the ballhandler as he gets past the pick. As this happens, the Celtic originally guarding ther ballhandler needs to give him up and dive under the pick to get ibetween the pick-setter and the basket to stop the pick setter from rolling for an easy dunk.
If you do that with Al (and to some extent Rob), they can generally stay in front of the ballhandler and take away the easy drive to the basket. If they do this with Kanter, it is almost the same as giving a free layup.
So, with Kanter on the floor, they need to do something different on pick and rolls, and that something can be drop coverage. When Kanter's man sets a pick, rather than trying to pick up the ballhandler, Kanter stays back, nearer the basket, and reads the play. Let's say Marcus is on the ballhandler. In switch coverage, Marcus needs to switch onto the pick setter and deny the roll. In drop coverage, Marcus needs to stay on his man, going over the pick if the balhandler can shoot, under it if he is bad enough. Assume the ballhander can shoot - depending on how well he uses the pick and how well Marcus goes over it, he may get totally free of Marcus or, more likely, get a step on him. If he does, Kanter needs to be in his way so that he cannot cruise in for a layup. If Marcus stays on his man over the pick Kanter can pick up the roll man.
Kanter is a good rebounder at both ends. Since the Celtics miss more than their share of shots, they can play for second chances more when Kanter is in. They can give up fewer second chances to the other team.
Ime's alternative is to give more minutes to Horford, Rob, and even Grant at the 5 because they can do the style he wants to play.
Anyway, Kanter wasn't the sole example of this - just an obvious one.
As a general matter, I don't think Ime needs to abandon eveything he wants to do, but he needs to incorproate things that play to his actual team's strengths and weaknesses. Forcing them to try to be the Tim Duncan Spurs overnight (or ever) is not the right answer.