The vibe around here is pretty negative about turning it around and being able to have a championship quality roster going into next year. I think it's very possible and here are some very realistic possibilities:
Sign Kenyon Martin to MLE/Let Davis walk and sign Carl Landry
Sign Kelenna Azubuike who I feel is very underrated coming off an injury. He had some excellent years in GS.
Resign Delonte West
Trade Bradley and this years pick for Mikel Pietrus, very good swingman can hit the 3 and defend
Resign Green
Sign Kyrylo Fesenko a center for the jazz who is a FA and has shown he is not afraid to bang down low.
All these things could happen under our current cap and a lineup of:
Starters:
Rondo/Ray/PP/KG/Jermaine
Bench:
Delonte/Pietrus/Green/Martin/Landry
Deep Reserves:
Azubuike/Fesenko
I feel like these moves would make our roster extremely deep, an immediate championship contender and all of these are very possible.
The Celtics are way over the salary cap. We still don't know if the new CBA will allow exceptions but let's assume it will. This is close to impossible to happen.
C's give K-Mart the MLE, the rest will have to be paid in vet. minimum. Fesenko might but the others, especially Carl Landry will get more money elsewhere. Azubuike will get more than the vet. minimum somewhere else. C's can probably sign Delonte for the minimum though. So unless Landry and Buike agree to the vet. minimum, the C's can't sign them.
Trading for Pietrus is not allowed because C's will be over cap.