There are about eight major cruise lines operating ships out of the U.S., each one accommodating anywhere between 1,400 and 5,600+ passengers. There are pros and cons with ship size, and it comes down to a matter of preference: amenities vs. personalized experience. Think of it in terms of a hotel stay – a mega-resort offers numerous restaurants, spa services and activities; while a bed & breakfast offers personalized attention and the opportunity to interact with other guests.
All ships are sized proportionally to their passenger count, and there are enough lounge chairs and dining tables for everyone. But if you strike up a conversation with another passenger on a mega-ship on Day 2, you might not run into them again until Day 7 (if at all).
Small ships may not have extensive spa services, multiple specialty restaurants, or Broadway-style shows, but they make up for it in experience. Don’t be surprised if the cruise director remembers your name, or your waiter remembers that you prefer decaf coffee with dessert. Small ships also have the benefit of being able to visit more ports – some of the larger cruise ships simply can’t fit into some harbors!
For a first-time cruiser I may recommend a mid-sized ship, between 2,500 and 3,500 passengers. This will give you a good balance between personalized service and access to services/amenities.