KTM and I were having this discussion because I am working on refit dreadnought conversion parts for the 1/350th refit, but I know there are questiosn about what should be the "True" refit dreadnaught. The image you posted is the standard one everyone knows, but I have heard several people say that the secondary hull needs to be longer. I have also seen scematics with a shuttlebay inthe front and second deflector dish in the back. This would be more of a true refit of the classic Franz Joseph schematic.
Let us know your thougts.