Chad Ford has suggested that the Wolves offered Al Jefferson for Troy Murphy's contract. It would definitely be an improvement from a talent standpoint, but the issue, as always, would be the contract. Jefferson is a very good player, and should be fully healed from his knee surgery, I think. He's probably better than any free agent that we could get next summer.
However, it might be worth saving the cap space in anticipation of the new CBA being much better for ownership. In that case, we would want as few big contracts as possible, then we can pick up free agents more cheaply (potentially).