I still don't understand how anyone could think signing a top free agent in the prime of his career and drafting 3rd in the same summer is anything less than a great offseason. Your expectations are out of wack if that is anywhere less than good. Even thinking it was simply 'good' is a odd to me, but not a big deal.
You are really out thinking yourself if you are coming out of this summer believing the Celtics had an average or below average offseason. Teams don't sign top players and draft top picks in this league often if ever, and the Celtics have done it two years in a row.
I gave the summer a B- for a number of reasons.
First, we had the 1st pick and traded back to get the 3rd pick and an unknown future pick. In the process, we gave up a chance to pick up the two most highly regarded prospects from the draft to select someone else, who many felt wasn't even the 3rd best prospect. I understand Ainge really liked Tatum and the trade probably saved Ainge some face, but I still think it was a bad trade on the whole.
Second, Ainge knew for a number of weeks that in order to sign a max level free agent, he was going to have to move Smart, Crowder, or Bradley and likely would need to waive Mickey and/or Jackson. It appeared that he was scrambling around and settled on the Bradley/Morris trade at the last minute. Had he been a little more proactive, especially before the draft, I feel he could have gotten better value than Morris and certainly shouldn't have had to give up a 2nd round pick in the process.
Third, I was very disappointed that Boston didn't even seem to try to acquire Butler or George, two players that were traded for value that Boston could have easily eclipsed. Butler and George are also both better than Hayward and frankly I'd rather have George and Bradley then Morris, Smart, Crowder and a future non-premium 1st (even if that cost Boston Hayward). I think Ainge really missed on not landing George. He could have been a real difference maker and the difference between losing to Cleveland or beating Cleveland. And I understand why Ainge didn't go harder after Butler (i.e. he loved Tatum), but I'd rather have Butler and 16 than 3, Smart, and Crowder (or whatever the package ultimately would have ended up as if it was in that range). I just feel Ainge was so set on using cap space, that he let better players go for relatively inexpensively that he shouldn't have.
So for me, on the whole I rate the summer as a B-.