Steve Bulpett (who I respect more than any other Boston basketball journalist) has repeatedly asked the question: Why can't Rob be like Bam? He asks it rhetorically, as he certainly believes (as do I) that Rob has the potential to be for us what Bam is for the Heat.
Rob should study tape of Bam Adebayo all off season. They are very similar in terms of height (Bam only 3/4" taller). Rob has 2-3" advantage in wingspan and standing reach. They both weighed about 240 lbs entering the NBA, although Bam seems to have added more muscle than Rob since. Rob is more athletic than Bam in terms of jumping ability and fast twitch quickness.
Both have demonstrated superior passing skills.
Where Bam has separated himself from Rob (and most every other NBA center) is his ball handling. He can take it up the court, and often does, to set up a play. He can make a move, like a power forward, off the dribble. Rob is just starting to show an ability to do this. I hope the Celtics spend the off season having Rob work more on his play making off the dribble. It is a skill that can be taught with practice. Jaylen Brown is Exhibit A. He was a horrible dribble penetrator his first 2-3 seasons. He has developed to become a quite decent one, subject to the occasional meltdown when he tries to do too much in traffic (usually on fast breaks, is my observation).
Rob can also hit the weight room to add strength and muscle. Bam is able to hold his ground better against bigger guys, although he too like everyone will struggle against the Embiids of this world.
Neither of them are 3 point shooters. And I hope the Celtics don't try to spend a lot of time developing Rob's 3 point shot.
Far more time should be spent on building strength and ball handling. I would love to see our team build around Rob as the center of the offense. He is such a skilled and willing passer. He really makes the ball move. He is the guy best suited to implement Brad's offensive schemes, similar to Al Horford when he was a Celtic.
Rob will always struggle against guys like Embiid, defensively, and that's okay. Bill Russell struggled mightily against Wilt Chamberlain. Yet the Russell's Celtics usually beat Wilt's Warriors/Sixers/Lakers. There are ways to deal with Embiid scheme-wise. I have been advocating putting a Smart and/or Grant Williams and/or Semi on him, taking charges, causing double teams, creating havoc. Play Rob off of him, put him on Simmons.