I'm curious. If the Knicks refused to trade Melo to Boston could we potentially clear enough space to get him? Would it be cheaper to do that then trade directly with the Knicks? Could we get someone to take on Gerald Wallace and/or Green for picks?
I think it is theoretically possible.
Step 1: Brandon Bass, Joel Anthony, Kelly Olynyk (because he makes more than Sullinger), and draft picks for Kevin Love
Step 2: renounce all free agents, the TPE, and the MLE
Step 3: cut all unguaranteed contracts
You're left with Love, Rondo, Faverani, Green, Sullinger, Wallace for $52.3m. If you can use whatever picks you have left over to do a salary dump of Wallace and Green, you can give have enough money to give Carmelo Anthony what he wants (due to cap holds for empty roster spots, I think you might have to move both of them to give Melo near-max money), with maybe as much as $10m in cap space, the room exception, and the veteran's minimum to find a starting SG, have someone better than Faverani as your starting center, and fill out your bench. You might have less than $10m if you are taking back smaller contracts as part of that salary dump.
Would you rather have Carmelo Anthony and whatever that cap space gets you or would you prefer Jeff Green, Avery Bradley, the ability to use the TPE and the MLE to add to your roster, the opportunity to use Bird rights to sign guys like Humphries and Bayless for your bench, all the picks you would have to use to get another team to take on the contracts of Wallace and Green, and the chance to use Wallace's contract as trade ballast a year from now?