We have plenty of chances to improve, even if we're over the cap we still have exceptions and a good amount of expiring contracts, and we could potentially sign and trade davis for a player's draft rights after the draft, we would have to take on extra salary, but we could potentially get a useful player back, too.
For example, we COULD do this...
Trade for the draft rights to Chase Budinger, after draft sign and trade Davis to New York for Jared Jefferies and Earl Clark's draft rights (Or insert your favorite player in that area of the draft)
Trade Tony Allen and Brian Scalabrine for Barbosa from Phoenix, add Giddens, Pruitt, or Walker if Phoenix wants.
Sign Ron Artest or Shawn Marion for the MLE, and then Mcdyese for the LLE, re-sign Powe to a minimum deal, let Eddie, Mikki, House walk
Rondo/Barbosa/Pruitt
Allen/Barbosa/Budinger
Pierce/Marion/Walker/Clark
Garnett/Marion/Powe/Clark/Jefferies
Perk/Mcdyese/Powe
All of which is probably so unlikely it's not even funny, but I wouldnt be opposed to any of those deals. And then BOOOOOM back to the finals, and on to 18.