This has been a long time on my mind. All of us have credited Ainge as being a superb GM when it comes to drafting. Free agents have been different though. Scalabrini has been a long time coming to prove his signing, PJ was great as well as Eddie House. However, I never cared for Cassell last year and Scott Pollard was a wreck.
What about this past summer? O'Bryant was a terrible signing. Giddens was not a good pick at all either. Walker could still pan out though. Why was Cassels signed? If Ainge had signed someone else instead of O'Bryant we would not be in this same big man pickle right now. It is his fault. I think there were other players better than Giddens still on the board as well.
Assuming by offseason, you literally mean the months between last year's Game Six victory and Opening Night:
2008-06-26 Celtics J.R. Giddens first round pick (#30 overall)
2008-06-26 Celtics Semih Erden second round pick (#60 overall)
2008-06-26 Celtics rights to Bill Walker cash trade with Wizards
2008-07-16 Celtics James Posey lost unrestricted free agent (to Hornets)
2008-07-16 Celtics Patrick O'Bryant signed unrestricted free agent (from Warriors) to a 2-year, $3M contract
2008-07-21 Celtics Eddie House re-signed unrestricted free agent to a 2-year, $5.6M contract (second year is player option)
2008-07-21 Celtics Tony Allen re-signed restricted free agent to a 2-year, $5M contract
2008-08-14 Celtics J.R. Giddens signed first round pick to a 2-year, $2M contract with a 2-year, $3.1M team option (date 08-26 per NBA)
2008-08-22 Celtics Bill Walker signed second round pick
2008-08-22 Celtics Darius Miles signed free agent to a 1-year, minimum contract
2008-09-10 Celtics Glenn Rivers (Doc Rivers) re-signed as head coach to a 3-year, $16M contract extension through 2010-11
2008-09-29 Celtics Sam Cassell re-signed unrestricted free agent to a 1-year contract
2008-10-20 Celtics Darius Miles waived
2008-10-28 Celtics Danny Ainge promoted to president of basketball operations and re-signed to a 3-year contract extension through 2012
2008-10-31 Celtics Rajon Rondo team exercised contract option for 2009-10
None of the draft picks have done anything, although getting Walker for cash was a good move.
POB and Cassell have done nothing.
House was a key resigning. Tony Allen has, as usual, shown flashes.
Waiving Darius Miles might have been a mistake, and might not have.
On the above alone, Ainge deserves, what, a C? A C-?
Prudent use of the team's assets still allows for additional in-season signings, as others have pointed out. If the Celtics acquire a FA or two that allows for a title defense, then his offseason grade rises. If they stand pat, it falls.
All this to say, the only real grade you can give Ainge at this point is an incomplete.