I don't think so. Right now I don't think we are any better. Horford is a big upgrade over Sully but whomever takes over Turner's minutes will be a downgrade at this point. 48 wins again sounds right to me, second round will be based on who we play again.
Frankly, I think you're nuts about the Cs are not any better right now. Currently there's been one gain (Hortford) and one loss (Turner) of established meaningful players. Hortford >>>> Turner. That's it and it just may be that simple.
Then there's also been the acquisition of the #3 pick in the draft in Jaylen Brown. This is also a meaningful acquisition.
Then there's the natural maturity of a group of young players. Smart. Rozier. Hunter. Mickey. Odds are that at least one of those guys will get significantly better this season. But because the team is so young there's no real offset on the older side. Amir perhaps but how much worse would you expect him to be?
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That's the simple analysis. But let's look at what was lost when Turner departed and how it gets replaced. Remember that if you bother to do a search you'll find that I've been a Turner supporter even at times when most of CB couldn't stand him.
Turner is a jack of all trades player. He's a decent but not good scorer, rebounder and can run the offense. He's only acceptable on defense. He can't shoot from outside at ALL. What he offered the team is a guy who could play off the bench, help win the 2nd team battles and could play backup point guard. He was one of the few Celtics who could create his own shot so long as he was playing against 2nd tier guys. He was a valuable steadying influence on the court and a good pro. He was also lucky that Brad put him in situations and with players that helped him to succeed.
But I believe the Cs already have replaced his capabilities. Guys like Rozier and Brown all have roles to play and quite likely will be better in individual areas than Turner was. We should have a backup SF who can put the ball on the floor and create his own shot. We should have the backup PG who can penetrate and run the team. We have guys who can come in and steady a younger 2nd team. We've got guys with the length, the speed and the game to fill every role that Turner had. No, it's not all the same player but these guys may very well be better in those individual roles than Turner was.
I wish Evan the best and appreciate his many contributions. But there may not be a good place for him on this team anymore. I think the Cs may have grown past his abilities.