First, I am of the opinion that Greg Monroe is the best young true center who also has the skills of a stretch PF, that is remotely available. I believe he still has a lot of upside and is orders of magnitude better than Asik. He can be the long term foundation at center of the Celtics.
I also believe that it will take Rondo to acquire Monroe, or any quality center, and it will take Rondo to move Wallace's contract, which is in my mind a highest priority.
Detroit Out: Monroe, Stuckey, Villanueva Detroit In: Asik, Wallace, M Brooks, A Brooks, Rockets 1st round pick 2015
Houston Out: Asik, Lin, Brooks, 1st round pick Houston In: Rondo, Stuckey
Boston Out: Rondo, Wallace, Brooks Boston In: Monroe, Lin, Villanueva (expiring) Detroit second round pick 2014, Detroit 2nd round pick 2016
Lin is a temporary but very capable solution at PG, Villanueva expiring combined with Wallace salary dump can land a good FA next year. Monroe fill a huge long term need.