Do not let the size full you. Allure of the Seas is a fantastic ship. As some reviews have mentioned, it can be filled to capacity and you never feel crowded. We never had trouble finding a spot to eat in the Windjammer buffet, the lines moved quickly at the Flow Riders, dinner with assigned seating was efficient but relaxed. For a HUGE ship, Royal still masters the art of customer service. The entire staff is friendly and some will remember you after a few interactions, even with over 5,000 other passengers to serve. The captain even stopped by while we were having a drink one night to say hello. Despite large groups of teenagers roaming the ship on spring break, the staff stayed patient and they genuinely seem to enjoy their jobs. So if you were concerned about customer service and the mood of the staff, don't be. You won't be disappointed. I know most of the other reviews have covered the features of Allure in great detail - our main concern was if we could get great service on a ship as huge as Allure and we were 100% satisfied. Our last cruise was on the Carnival Dream and we thought the crew was going to mutiny at any moment. Not so on Allure! Here are some quick pros and cons:
Pros: So much to do. You won't get bored. See as much as you can at the Aqua Theater. Check out Central Park and the Rising Tide Bar. The "Beach" pool is a great spot.
Cons: Comedy club needs to be bigger. It booked up immediately and the waiting list is huge. I would like to see Royal consider a larger comedy club with multiple comedians throughout the cruise. Dining-wise, Rita's Cantina is probably not worth the additional charge. For entertainment, I would scrap the shows Blue Planet and Chicago. I was half asleep in both of them. Trying to sit through those types of shows after a long day in the sun with several beers and cocktails is challenging. As for the crowds, the only time it was crowded on the pool deck was on a particularly windy day at sea. 5400 passengers were competing for spots that blocked the wind. But, Royal does a great job at preventing the rude cruisers from reserving deck chairs and disappearing for hours at a time.
Helpful Hints: Avoid spring break unless you're traveling as a family. There were teenagers everywhere. Just being typical teenagers but when there are dozens of them hogging the hot tubs at night, pressing elevator buttons for fun, and trying to sneak into the clubs, it can get annoying. Still, they were better behaved than some of the adults you'll find on Carnival ships.
Take a taxi from the cruise port. There are plenty available and it will probably be cheaper than prearranged shuttles through Royal Caribbean. If you are undecided about excursions, skip one or two. You can still get off the ship to walk around and enjoy the ports and you'll have some more money to spend on board. Boredom is not an option on this ship!
Summary: Do not let the size scare you. Unless you require a personal butler or have a phobia about being around large groups of people, you will enjoy Allure of the Seas. It is a ginormous, fun ship to be a part of. You'll still get the best combination of customer service, value, and quality available and remember, you're on the largest cruise ship at sea!