I second Raoul's suggestion. You are somewhat limited when you want to do a shorter cruise as the cruise lines use their older ships for those itineraries. Also, not all cruise lines offer cruises less than 7 days. The Enchantment sounds like it would suit your needs (I am hoping I will have a chance to sail her when the renovations are completed.) If you are not partiers and it comes down to a choice between Carnival and Royal Caribbean - choose RC.