NX was smaller and had a much smaller crew complement to show it was an older ship. Also food, water, and machinery would take up more space because the technology was more primitive. Having no starbase support network they probably carried a lot of spare parts (they were able to build two new phase cannons from scratch in "Silent Enemy").
I read somewhere that Galaxy class ship complement varies according to the mission. So 1014 crewmen was not necessarily a fixed number. Also TNG Technical Manual claims Galaxy class ships could evacuate up to 15 000 people, so they probably had a lot of extra space. Not to mention cetacean ops and supposed huge mall/grotto for crew comfort
I read somewhere that Galaxy class ship complement varies according to the mission. So 1014 crewmen was not necessarily a fixed number. Also TNG Technical Manual claims Galaxy class ships could evacuate up to 15 000 people, so they probably had a lot of extra space. Not to mention cetacean ops and supposed huge mall/grotto for crew comfort
