Well start with the fact that they let you cram more sailors on board than you would be able to do in real life, have them 'aquire' magical skills while at sea and the basic premise is fubar.
But its a game.
Its up to you the player to fill every single slot (a dedicated damage control team
) if you want.
Its a game.
Throw all the CPO's off the boat and start with scrubs for the lot.
Its a game.
So its up to you the player to 'control' the crew makeup and quantitys, play it arcade, play it 'realistic' its up to you.