I pressume gunboats are the corvettes/frigates and due to all the automatization and cost efficiency would employ very small ammount of crew. I find such gunboats as rather expendable and you do not want to risk many people.
Cruisers would be much bigger than real life counterpart (if freelancer was scaled right) but then again, automatization would keep crew requirement in place as the hull grows twice or thrice as big if not even decreasing the number of people.
Battleships on other hand need way more people to run it. Vanilia-wise they were performing carrier duty and mobile operations base role. It's not the crew we are talking about here but their security, pilots and personnel that would keep entire party together like mechanics for snubs stationed onboard.