Panes are much faster, they are a cheaper form of transportation and they are safer. Ships are not really even used for travel any more, just for luxury cruises and shipping product. I would choose a plane if my destination was the goal, and a ship only if I didn't need to get anywhere on a timeframe.
When traveling overseas, I personally want comfort, necessities and activities. A cruise ship offers all three of these. Though the cost and time might be greater to get from point A to point B, you get a worth while experience. You get the comforts of home, get to sit by a pool, and get to eat like a king or queen. Plus, once you reach your desired destination you are well rested for your adventures ashore.