If Kyrie walks, then the team looks towards the future and needs a younger PG than Conley.
I would make a hard push after Kemba if he decides he wants out. Charlotte will need something in return for a loss of Kemba and I think that Rozier would be an attractive piece for them.
So a deal centered around Rozier, filler and one of the later picks for Kemba makes sense. Then use other assets to upgrade the Center spot. (Brown, Morris S&T) - looking at Bamba, Turner
(This Hinges on Kemba wanting the Celtics and wanting to help Charlotte out by allowing, and charlotte wanting a sign and trade to happen)
And if No Kyrie, then No Davis. so I instead would look long and hard into a deal for Bamba (Vuc will be going back to Orlando, I dont see any doubt of that) or put out feelers on Turner.
Personally, I think Bamba has alot of upside and a lower cost as Orlando still has some pretty big holes that Boston can fill. (Rozier S&T for Bamba.
Then I would just keep Smart or Brown as the PG and let Hayward actually run the offense and have smart or brown just defend the lead guard on the opposing team and go into the season with that and reassess a few months in. Draft would most likely net a nice young SF (Little, reddish, Rui, Doumbouya)
Semi - Draft
Team easily makes playoffs IMO, and maintains alot of asset moving forward.