This post definitelty deserves a TP! Fairly well written, and obviously the OP put a substantial amount of effort into it.
As for the actual content, some I agree with, some I don't. As Roy pointed out earlier, your point of reference seems to vasilate between "at the moment" and "hindsight". I don't think it can be like this. Also, I just see some of the situations differently.
I have a lot of thoughts on Ainge myself, but will focus on just one aspect. The rest would require a post similar to the OP's in length.
-Ainge's off-season/in-seaon moves during the Big 3 era have been average at best.
The Great: Posey, House, PJ Brown, Bass for BBD. These moves need no explaination, they are that obvious.
The Good: Sheed, Shaq (for the value he was signed at-not necesaarily results), Peitrus, West (again for value-not necessarily results). Each contributed in a meaningful way, but had there downsides as well. Overall, these players were decent signings.
The Bad: Letting Posey walk, letting TA walk. Not giving Allen the 3rd year on a contract was a mistake. The additional $3-$4 mil next year would not hamstring us as much as people think. Also, we wouldn't have likely needed to make the Perk trade. It may not have changed the outcome last year (Rondo going down ended everything), but it was a bad move none the less. Danny let TA walk just as he was coming into his own. Suffering through all of his ups an downs only to let him walk just as he reaches his potential was bad. Also, letting Posey walk was bad too. People like to use Posey's contract against him, but realize this. Posey's deal will be expiring this off-season. Same as KG and Ray. Our cap space would not be hurt. Furthermore, having Posey on the books would not have prevented us from signing a single player signed since. This supposed contract issue is a misnomer. We have not been able to find a legitimate back-up for Pierce since.
The terrible: O'Bryant, Mikki Moore, Sheldon Williams, Murphy. Not much needs to be said here. These players stunk.
Like I said, overall these moves are average at best in totality. Considering, what has been at stake, I'd say Ainge gets a C- for these moves. Some helped us win a title, others may very well have hurt.