I liked Restaurante Las Delicias at 5th Ave. north of Constituyentes. It's not typically mayan food but good mexican food at a reasonable price and the decoration is very nice. And I like that you can see when they are cooking. They used to have very funny and attending waiters. (Last time I was in Playa is one year ago). For breakfast there is a huge palapa restaurant 1 block north from las delicias. I don't remember the food there but the palapa was impressingly beautiful. I don't remember the name. You will find thousands of good and beautiful places to eat.
Enjoy your vacation.