You'd really have to ask a musician who's done this type of work. I think it depends on what kind of music you play, I imagine that jazz is more useful than classical for example. Most of the musicians on the ships are lounge-style performers, small bands with a singer, solo pianists or guitarists, playing easy listening music (Barry Manilow/Bert Bacharat) or jazz/blues.
Put a new post to ask, I reckon there must be a few musicians among the people who read this board.
Sorry I can't help more