When this current squad's run is over, the next Celtics contending team will be built through trades and draft picks, not free agency. So, those who advocate not signing anyone past 2012 (when Kevin Garnett's contract expires) in hopes of creating massive cap space are completely and utterly wrong about how to build a post-Big Three Boston squad around Rajon Rondo.
As we are about to find out, clearing cap space to sign big free agents doesn't mean you will sign any. Teams will panic and overpay second-tier free agents when they don't get first-tier free agents. And 2012 doesn't look like a good free agent class anyways. Boston has never been seen as a great free agent destination. It's better to develop trade assets to acquire a star disgruntled by having to play for a perennial non-contender. With some of these teams supposedly seeking to follow the Celtics model and bring together multiple max contract guys, some of those teams are going to fail to develop chemistry and look to move one of their big contracts a few years from now.
In rebuilding, the Celtics need to acquire and develop trade assets. However, this has to be tempered by the fact that Boston is still a legitimate title contender. Even a 10% chance means you win once a decade on average, and it's foolish to turn that down if you care mainly about winning titles.
All player movement should be evaluated in terms of how it impacts Boston's trade assets. For example, the mid-season acquisition of Nate Robinson arguably had more potential impact beyond the 2009-2010 than during. It turned Eddie House, who was clearly not a trade asset, and JR Giddens and Bill Walker, two trade assets with declining value because they were clearly not going to play under Doc Rivers because of their inability to contribute on defense, into Nate Robinson, a player who other teams might actually want. Since the Celtics hold Robinson's non-Bird rights, it means they can sign him to a contract worth up to 120% of his previous contract. Since Robinson made $4 million last season, it means that Boston can offer just as much money as any team, unless that team is crazy enough to throw almost all of the mid-level exemption at Robinson. Eddie House signed a 2-year $5.6 million contract in 2008, while Glen Davis got 2 years for $6.5 million. If Robinson is resigned for a contract in the same range, he provides insurance that allows Avery Bradley to be sent to the D-League if necessary and brought along slowly, but is also a player that teams might be willing to acquire because they actually want him and not because of salary cap considerations. So, it makes a lot of sense to try and retain Nate Robinson unless the team decides that Robinson will regress and end up rotting on the bench as amalcontent. Personally, I would feel comfortable with Robinson as long as Doc Rivers also returns to mentor him like he did Rondo. Even if you think that Robinson isn't the best fit for this team as a back-up PG, as long as he is serviceable, he is a better option than a vet minimum pick-up who would be a slightly better player on the court in 2010-2011 because Nate has future potential trade value.
Which brings us to the Big Three. The idea was that KG, RA, and PP had their cotracts expiring in successive years and could be moved as expiring contracts. I think that's still a good plan. You just need to extend Ray Allen and Paul Pierce to make that work. That's why I advocate signing Ray Allen to a three-year deal set to expire one year past Garnett's contract. Now, if you can get good value in a sign-and-trade (I at one point envisioned sending him to Miami to join Dwayne Wade in exchange for Michael Beasley and Daequan Cook, but Cook got traded to Oklahoma City instead), then certainly the team should ship Ray Allen, but if not, then the team preserves value by re-signing Ray Allen. Arguably, RA is worth more the Celtics than any other team since re-signing him means that the team doesn't have to look for a new shooting guard with the MLE or Sheed's contract when the team is already desperate for a big and it means the team still has a chance to trade him later. So, it makes sense for Boston to be willing to give Ray Allen a bit more than what his future on-court performance dictates, if necessary to win a bidding war.
I would give Paul Pierce a reasonable extension for one year past a new deal for Ray Allen (which means a four-year deal). Manu Ginobelli recently received a 3-year $39 million dollar extension. Paul Pierce opted out of a final year worth $21 million. Add the two together and you get four years for $60 million, restructured to help the ownership pay less luxury tax. Kevin Garnett would be re-evaluated after the next season as to whether or not his value as a player is more than his trade value as an expiring contract.
With respect to draft picks and free agent signings, the goal is to look for players who can be part of a package for either a high lottery pick or an established star so that you can get a potential All-NBA talent next to Rajon Rondo. That usually means taking the best player available instead of drafting for need, but probably also means that draft picks who have a shot of contributing immediately and creating trade value through their play are better choices than projects who have no shot of playing the sort of defense that will earn minutes from Doc Rivers. For free agents, that means avoiding signing anyone to potentially untradeable contracts. Long contracts to young talent based on potential that may not pan out are to be avoided. If you can't fill out the team signing free agents who Boston might want to lock up long-term or who another team might want to trade for, then the team is better off using salary slots like the MLE on veterans signed to shorter contracts, two to three years so that they can be traded as expiring contracts, but nothing that is four or five years long.
Don't make any trades for players with bad contracts for the sake of getting younger or making a change. The only reason you accept a bad contract in a trade is if you are getting rid of an even worse contract or if you are getting draft picks as compensation.
So, basically, my suggestions include signing Ray Allen through 2013, Paul Pierce through 2014, and Nate Robinson to a reasonable contract for a bench player that is large enough to allow him to be swapped for something meaningful like a former lottery pick.
In an ideal world, two years from now, the Celtics can send Ray Allen, next year's draft pick, future picks, and some bench players for a disgruntled player of the caliber of Dwayne Wade or Carmelo Anthony. Maybe Kevin Durant will wake up one morning and realize he's in freakin' Oklahoma.