This is a pirate based game correct? Make it feel like that! I feel like the current crew titles (Captain, Co-Captain, Officer, Veteran, Member, Recruit) seem a bit unpiraty. So I did some research and here is what I suggest you change it to.
Captain (This one was fine as is)
Quartermaster- In terms of a pirate this was basically who had authority over everyone else besides the Captain. If the captain had other duties to perform or couldn’t lead for any reason the QuarterMaster would be most likely to take over
Sailing Master- These are the people who sailed the Pirate ship. They required education and reported directly to one of the higher authorities
Boatswain- There are usually multiple Boatswains in a crew. The Boatswains usually have their own sector of work. For example, one might command the gunners the other might command the people that lower/raise the sails
Gunner- The gunners are the people who aim the actual cannonballs at the enemies (this is one Im debating on changing, so if you have any suggestions lmk)
Powder Monkeys- These people are young boys that helped the Gunner’s. They were often treated very badly and paid very less also