I'm including 2 engine rooms. The season 1 engine room would have to be a little smaller than the set to fit within the confines of the hull at the back of the saucer. The season 2/3 Engine room is the real Warp Engine control room on the hanger deck in the secondary hull. The pipe structure sits between the engine room and the hanger area and is more in the middle of the secondary hull rather than pushed back toward the hanger and pylons. The plumbing to the pylons passes over any part of the hanger area that is forward of the hanger bulkhead. This allows the entry seen in Journey to Bable to be forward and the view into the hanger would be of the inside of the clamshell doors (there are no details on the far wall so it could literally be any of the walls in the hanger, but the inside of the doors is the most logical to be so featureless). I see no need for a 2nd pipe structure in the secondary hull so I have not included one. I consider the pipe structures to be the main energizers (which use dilithium to convert the warp core plasma into energy the ship can use). The saucer energizer provides power to the saucer and main weapons and shields while the secondary hull one provides power to the deflector, aft weapons, and the warp drive system. Auxilliary power is located in the saucer.