In years gone by, mid-ship used to be the most popular location on board, with only the most comfortable sailors preferring cabins elsewhere. Mid-ship cabins were preferred for their stability but this has become less of an issue for modern ships, which are far more stable than those of previous years thanks to increasing technology.
Today, some of the highest stateroom categories are located at the forward or aft of the ship, rather than mid-ships. Aft facing balconies and suites have become extremely popular and are perfect for sun lovers and people who love taking in the views; thanks to its position, accommodation in this location receives all-day sunshine and the best views for sail aways.
Choosing between port or starboard often comes down to personal preference. If you are cruising a roundtrip itinerary to and from Southampton, then you will get sun on your balcony either the way, whether that is on your way out or on your return. If you are doing a transatlantic voyage or an Alaska cruise up the Inside Passage for example, then your choice of cabin side is more important. If you are opting for a balcony cabin so that you can catch the best views from in privacy, then it is important to speak to your sales consultant at time of booking and ensure that you choose correctly between port or starboard for that specific itinerary.
The way the ship docks in port is another factor that may influence your decision between port or starboard, though this is difficult to predict as it depends on berth availability, the weather and several other factors.