Best advice we never received: go to the Guest Services desk on day 2 or 3 and ask them to remove the automatic gratuities (the per person, per day)- we prefer to pay via envelope at the end of the cruise.
Now that we are 15+ cruises in, we treat the ship as an all inclusive resort with an ever changing view out the windows- rarely leave except to walk a new port or for a new experience (George Washington House tour led by the head of the National Trust in Barbados being our latest greatest)