Thanks all, that's about what I was expecting.
One thing I do at the outset of a new career or war patrol, is to dismiss those "preset" crew members who are potential deadbeats and replace them with more competent personnel: for instance, I can't see the point of having a seaman 3rd class mustered as a watchman, when he has a mere 10 watch points and his other "abilities" aren't much better - I much prefer replacing him with a seaman 3rd class who has 50 watch points, plus some other reasonable point scores, particularly when he costs 0 renown points.