But (and this is my key point) it doesn't even matter. We have good players on excellent contracts (IT, Crowder, AB), we have some young talent (although I must admit JRHunter and Young were big disappointments), we have the cap space and we have a ****load of picks.
This team was expected by most to barely make the playoffs this season, and we almost made it to the 3rd seed; I really don't see the reason for the pessimism.
I agree, and I'm not sure what pessimism you're talking about. To be clear, my response to the OP was that I would expect this team to make the playoffs again if the same basic group comes back. They've shown more than enough for us all to believe that, barring a major injury to Isaiah, they'll get to the playoffs.
My thing is -- OK, so what? If the same group plus, say, Jaylen Brown, comes back next year, I think we can expect basically the same thing. 40-50 wins, maybe more if everything breaks in favor of the Celts, and a puncher's chance at winning a first round series.
That's not enough for me. It may be that FIREWORKS don't happen this summer. If they don't, I'd like to see the team move on from some of these guys -- Turner, Sullinger, Amir, Zeller -- and explore creative options via trade / free agency to audition some different faces.
We've got a lot of nice but not great players on this team. This is a nice but not great team with some glaring weaknesses. I want to see an effort to address that, and maybe uncover a diamond in the rough or two, rather than sticking with known quantities.
I'd draw a comparison to the Raptors, who almost entirely revamped their bench with Cory Joseph, Bismack Biyombo, and Luis Scola, along with the addition of Demarre Carroll to their starting lineup, and it's worked out pretty well for them.
I just don't believe in saying "Welp, this team is young, they had some bad luck in the playoffs after a nice season, if we can't trade for a superstar let's just bring the gang back and do this all over again."
Especially when we know that if Ainge can't trade for a superstar, that probably means we've got another 2-3 rookies (at least) sitting on the bench.