Also, the cruise line seemed to try to "nickle and dime" us every time we turned around. Members of our group had purchased a "soft drink package", but the waiters always attempted to bring a canned soda (costs extra) instead of the fountain soda that was included in the package. You could get a pastry at the Mondo coffee bar, but the coffee there was an extra cost. (Free coffee was available at the Park Cafe a hundred feet away) Some food venues were free at some times and cost extra at others. There was NO coffee available at all until after 7 a.m. (a real trial for us early risers!) Johnny Rockets was an additional cost, and you could not even get your own separate order of fries. They plopped one basket in the middle of the table for "sharesies" for everyone. Yecch!On the plus side, the shows were superb, and the meals in the dining room were quite good. (It is difficult to eat with "party manners" every night sometimes) The stateroom was comfortable and our cabin steward was really sweet. I am sure his twelve plus hour days cleaning and carrying are hard, but he always had a smile for us.
Here's a hint. Skip Tulum Mayan Ruins excursion. It's a ride to two tourist trap gift shops and a visit to a couple of piles of rocks. Very little in the way of historical interpretation and you cannot get close to the piles of rocks. You can get some nice pictures, but for $89.00, they are pretty pricey pictures.
Over all, I do not recommend the Oasis. They enlarged the ship, added staterooms, theaters, restaurants and an ice rink, but forgot that all those extra people had to visit the buffet and get around the ship.