OOC
After creating the infrastructure only floor plan, I went to do some expermental layouts. That started with trying to verify what scale to use. It turns out that the scale used for the existing floor plan details is not at all consistent. I calculate 1127 squares across all 3 decks. To round things a bit, assume an extra 73 squares for content that is not part of the deck plans. Things like the turrets, landing gear, and maybe some 'buldges' for fuel storage. That brings the total to 1200 squares. For a 600 Ton hull, that is 2 squares per (displacement) ton, or 0.5 dT per square. However, the space shown as used for various features is radically different.
The launch bay is supposed to be 24T, but it consumes 84 squares. That is 0.29dT/sq. This should also be one of the buldges, since the launch bay should be more than one 'block' high to have room.
The fuel processors are supposed to be 4T, but they consume 18 squares. 0.22dT/sq
The medical bay, staterooms, mess, and rec room all seem to be about 1dT/sq. The 'about', is because technically the space used for the hallway should be counted as part of the rooms.
The main bridge is supposed to be 20T. It is shown consuming 25 squares, but if counter measures and enhanced signal processing are included, that gets close to 1dT/sq, the same as the staterooms.
The full engineering spaces, right out to the outer edge of the hull, is 171 squares. Reduce that by 31 squares for fuel storage and hull. The jump drive, power plant and maneuver drive total to 98T. Include another 5T for sensors, 20T for shield gets to 123T in 140 squares. Not too far off the 1dT/sq.
So average should be about .5dT/sq, and I see from .22 to 1dT/square. A significant range for something like floor plans.