As of today, I'd identify three glaring holes in this rotation:
A lack of cutters and ball-movers - to create off-the-ball action and a dynamic offenseThought this comment from Who on this point is great:
https://forum.celticsstrong.com/index.php?topic=100776.msg2702452#msg2702452Lack of shootingBoston lost an elite shooter in Irving, and two very good ones for their positions in Horford and Morris. Kemba has never been Irving's caliber except for a couple of seasons but it's plausible he'll be good enough if he can afford better shot-selection. Took a lot of shots last season and that might be the reason for his decline from the high 30s to the mid 30s that are his career average.
Kanter doesn't shoot the 3. Williams and Langford were mediocre 3pt shooters in college. Edwards shot 35% in high volume, which is promising, but likely not "good shooter right away in his rookie season" promising. Uncertain any of the rookies finds playing time even with the current roster anyway.
The team probably needs to acquire more long-range shooting and hope Smart/Brown/Tatum/Hayward improve on their last season.
Mediocre shooting would make the offensive issues mentioned above even worse.
Very weak defensive bigsKanter, Theis, Robert Williams, Grant Williams, Yabusele.
Hayward/Tatum. Ojeleye as another combo forward.
I'm not sure there's a worse defensive big man rotation in the league. There isn't a single quality big man defender in the roster.
Surely Ainge will add a defensive big to this group? It'd be baffling if he didnt' and added someone like Cousins.