If the E-D is indeed 642m long, how thick is the front of the saucer where Ten-Forward is supposed to be? Is there enough room for two decks there? One deck? Two full decks separated by Jeffries tube space?
Something else that also puzzles me. On the MSDs, the decks are something like nearly 4 meters tall. Why? A deck could just be 3 meters, or even slightly less. There don't HAVE to be Jeffries tubes EVERYWHERE. It's like there's a meter of free space over every ceiling on every deck, everywhere.
Most Trek ships don't have enough room for the complex ceilings seen in the sets. In Mr. Scott's Guide
and the old cutaway poster, the refit 1701/1701-A has 8' saucer decks, the height of the corridor ceilings, despite sets like sickbay being much taller. I prefer them to err on the side of caution and give too much space than too little.