One element to consider is the size of you luggage. Walking on the cruise, the bags you carry on will need to go through an xray scanner with you. While the xray machine appear slightly bigger than the ones in the airport, they are not necessarily the size of larger suitcases.
We were on a cruise last year, where someone tried to walk on with a large roller bag. It didn't fit in the xray machine & security basically had to open it and go through it piece by piece. Slowed down the boarding process as well as all the clothes & items had to come out of the bag. Personally, it was the not the way I would want to start a cruise.