I'm not a huge fan of the new deck plans, where ALL of a given system is in one large block of color coded squares. Anybody with any familiarity with ships at all knows that 'everything in one place' is an often-wished but seldom realize dream for shipbuilders.
But in this edition, the offices of the CO, Marine CO, the Chief Engineer, Flight Officer, and [aboard the Deepnight] the Mission Commander and Chief Scientist would part of their generous quarters allotment. The 'offices' allotment is probably for the administrative staff... the supply/logistics, personnel, intelligence people, etc. Even with the very high end computing capabilities of TL-15, a ship's administrative staff needs more room than a lot folks think.