Crystal Cruises strives for the sweet spot between the smallest luxury ships and the midsized mainstream ships. Its two oceangoing ships, Crystal Symphony and Crystal Serenity, are small enough to offer an intimate feel and excellent service, but big enough to offer variety in dining and entertainment. (The line also has yachts and river ships, but we won't address them in this story.) If you're considering a high-end cruise, here are six reasons why Crystal Cruises might be the ocean cruise line for you and three why it might not be.

You might like Crystal if…

You like choice in dining.

With Symphony's 2017 and Serenity's 2018 refurbishment, Crystal is adding more choice than ever before to its dining scene. It has traded assigned seating for open seating dining, so passengers can come to dinner whenever they like. Every night, there are five dinner options: the Waterside main dining room, Italian Prego, Japanese Umi Uma (by celebrity chef Nobu Matsuhisa), the Brazilian steakhouse Churrascaria and family-style Chinese Silk Kitchen. Plus 24/7 room service. Even the Waterside menus offer lots of choice with classic dishes and more modern interpretations every night.

You hate being bored at night.

On some luxury lines, you have dinner, go to the show and then get a drink. Every. Single. Night. On Crystal, your evenings will never be predictable. Some nights have two shows instead of one, a mix of song-and-dance revues plus guest singers, musicians and comedians. Musicians play live around the ship throughout the evening; you'll find a quartet playing music for ballroom dancing, soloists providing pleasant background music as you sip a cocktail and piano entertainers in the Avenue Saloon. A DJ gets the dance floor going after all the shows, while a dedicated movie theater screens recent releases.

You hate being bored on sea days.

Sense a theme? Crystal excels in enrichment. Guest lecturers, ballroom dance instructors, golf professionals, artists and bridge teachers are nearly always onboard to share their expertise with passengers. Technology-focused classes range from an introduction to the Windows operating system to making your own films with iMovie. The Magic Castle at Sea program brings magicians onboard to host intimate shows on sea-day afternoons.

You're cruising with the kids.

Crystal is probably the most family-friendly of the luxury cruise lines. Many cabins, including suites, have third berths or connect to adjoining staterooms to accommodate groups. Dedicated kids clubs -- with comfy chairs, toys, video games and more -- are staffed during holiday and school vacation periods and offer programming for kids ages 3 to 17. Kids even cruise for free as the third passenger in a cabin on select voyages (though of course, many of those sailings are during the school year).

You're not cruising with anyone.

Solo travelers are taken care of on Crystal, from the Ambassador Hosts (gentleman of an age who dine and dance with partnerless cruisers) and a dining program that reserves tables at the specialty restaurants for singles, so they don't have to dine alone or always eat in the main dining room. With plenty of activities onboard, solo travelers can easily meet others or fill their days without feeling lonely. Crystal's solo fares are also competitive; on many cruise, singles pay less than double the regular price.

You love theme cruises.

Crystal's Experiences of Discovery program features sailings themed around a variety of topics. Crystal on Broadway cruises bring aboard working cast members and creative professionals from Broadway to perform and lecture onboard. The line's Food and Wine Festival sailings gather top chefs, wine experts and mixologists to host demos, lead classes and offer tastings. Golf-themed cruises feature PGA instructors and star players, plus the chance for onshore play. Other topics include jazz, ballroom dance, fashion, film and mind, body and spirit.

You might not prefer Crystal if…

You need a large entry-level cabin.

If you like a smaller-ship sailing, but don't have the budget to book a suite every time, Crystal might not be the best line for you. Its outside and balcony cabins are smaller than the similar introductory categories on lines like Silversea, Seabourn and Regent. They don't offer walk-in closets and bathrooms are cramped. You won't find booze in your mini-bar either.

You want a ton of itinerary choice.

Crystal does a great job of sailings its ships around the world, but it does have the smallest fleet of all the luxury lines. That means, at any time, it does not have ships in as many locations as other cruise lines. If you want the widest selection of destinations while sticking to your favorite line, you might do better choosing another cruise line. (Then again, if you don't mind switching from an ocean vessel to a yacht, your itinerary options expand with cruises on Crystal's river ships and yachts.)

You prefer new ships.

Crystal refurbishes its ships every few years to keep them modern and fresh, but both were built in the 1990s and early 2000s. A new ocean ship isn't expected until 2022, and the line isn't committing to more than one new-build at this time. If you must have that new-ship smell with the latest in environmentally friendly cruising, in-cabin technology and out-there innovations, you'll need to book one of Crystal's new expedition or river ships -- or find another line.