I still think you're WAY officer heavy, but... Trek does that so it would be overlooked by most. I would actually see a lot of overlap between the departments. While everyone has a primary station they help out where needed. Security people would regularly be helping out in engineering when there's no fighting to be done, the scientists could help out in medical or operations if they're not actively researching, etc. You could use a janitor or two also. That ship doesn't clean itself yet.
Also, one doctor, one nurse and a couple of medical technicans would be more than enough for a ship of 80 or so people.