Kat:Here is another reason why prices are low in May. Spring break is over but school is not out yet. Very few families w/ school age children travel in May and the college kids are taking finals. However, don't think you wont run into kids. Many families with younger children like to travel during May because of the low prices and smaller crowds.
Is the Plaza Las Glorias becoming part of the Mayan Palace time share chain or the Palace Resort (Sun, Moon, Adventure) hotel chain? It sounds like, since it will be all-inclusive, it might be the hotel chain.
Palace Resorts bought Plaza Las Glorias and its sister hotel in Playa del Carmen on the beach directly to the south of the ferry pier. Both hotels are closed right now and being completely renovated.