I think you might be over-thinking things here. Dwight is a top-five scorer among centers, and Deron is a top-five scorer among PGs.
Having Dwight and Deron would lead to more offensive rebounds, it would lead to more mid-range space for our shooters, etc. We'd have somebody who could consistently convert down low, and a PG who could consistently shoot from outside.
If we could conceivably run a team out there of Dwight-KG-Pierce-Ray-Deron, I think we'd have a top-5 offense, no matter what the bench. No team has the defense to shut down all five of those guys.