Thanks all! Great points. I originally favored weekly itineraries that didn't have three days at sea for this reason, but given ninjacat123's good point, the captain might be less hurried with more sea days and perhaps that will help.
Rich: Wow, lots of experience already on these ships! Do you favor one of these ships more than the other (for any reasons in particular)? I have a 14 yo and a 19 yo - Holland America's offerings are less expensive but I know my 14 yo would prefer the activities on Celebration.