I think the Celtics have their eyes set on acquiring a center by two potential means:
1. Using the League Exception ($9,073,050). My gut tells me DeMarcus Cousins is that target but not sure if the market will dictate a larger salary for him. Alternative: Enes Kanter
2. A trade involving Jaylen Brown and other pieces to acquire a bigger name asset (Maybe a S&T of Vucevic from Orlando).
PG: Kemba Walker
SG: Jaylen Brown (insert Marcus Smart if JB goes out in trade)
SF: Gordon Hayward
PF: Jayson Tatum
C: DeMarcus Cousins or Nikola Vucevic
I'd be fine with that team. Cousins can be a loose cannon some times, but he keeps it pretty together when he's playing with a coach he respects, and I can see him Respecting Stevens. If Stevens can get Cousins to buy into the D, he's not quite as good as Horford on D, but size can help him, better scorer and can pass and is willing to.
NY has been reported in going after him if they strike out on KD and Irving, but Cousins may want to sign an other 1and1 to get his value even higher next summer. Unless NY throws a ridiculous amount of money at him. Just depends on if he's looking at a payday right now, or rings. He's in a weird situation, where he's still young, but came off the injury so who knows how much longer he can play at a high level. It's either money to set himself up for the rest of his life, and worry about ring chasing later, or ring now, and maybe money will follow that.