If you tend to get seasick, cabin location is really important. It is a question of engineering, really. The lower and more central you are in a ship, the less roll and sway you will feel. Even if you choose a balconied stateroom, choose the lowest level and the most midship one you can find. The higher decks and cabins at the very front (forward) or back (aft) of the ship will rock and roll the most.
Some lines offer gated-access suite complexes where some of the most expensive accommodations are arranged around exclusive deck areas, including private pools, whirlpools, fitness centers, sun decks, restaurants and lounges; MSC Cruises Yacht Club and Norwegian s Haven are two examples. Norwegian s studio cabins -- although tiny inside affairs -- also gain you access to a special lounge reserved just for solo travelers.
A concierge can take care of all those annoying practical matters you need to tend to on a cruise: making dinner and spa reservations, booking shore excursions, making requests of the front desk. Their services are included in the price of many suites, and on some ships the concierge has a desk in an exclusive concierge lounge where suite guests and high-level past passengers can snack, drink and relax in private. Concierge-level cabins may also come with in-cabins amenities including welcome drinks, fruit baskets or afternoon canapes.
Inside cabins with no views at all are typically the smallest, cheapest cabins onboard. They are great options for budget-minded travelers who do not intend to spend a lot of time in their stateroom, or who want to sleep all day in absolute pitch dark. They are less ideal for cruisers prone to seasickness, those who need natural light and groups who require a lot of in-cabin space. Not everyone will be happy in an inside cabin; it is worth upgrading if the lack of light will put a damper on your vacation.