There are a lot of places you can stay, from booking an airbnb.com to save on accommodation or luxury hotels. I traveled over the summer of 2017 and stayed at Grand Hyatt hotel, and we had a great time, it is a very nice hotel. There are a lot of places to stay it depends on what part you want to stay, near the 5th avenue where there are shops restaurants, hotels, or like in the Riviera Maya ( a little outside of playa) to search for peace and quiet. Like in Mayakoba there are a few hotels like the Fairmont: http://www.fairmont.com/mayakoba-riviera-maya/.
It is a underground caves discovered recently, you have to book ahead of time, it is a very cool place to visit, you will have a guided tour and they explain everything on the caves.
A beach club to spend the day http://www.mamitasbeachclub.com/
There´s a place to have breakfast on 5th avenue called Chez Celine, a french place, with delicious pastries and more
Take the ferry to Cozumel, and explore the island, it is a great place to do scuba diving, or just relax at some of the beaches.
This park has it all!, underwater river, snorkel, night shows, everything to spend all day.! http://www.xcaret.com.mx/
Spend the last day relaxing at the beach, maybe a nice afternoon massage, and stroll around La Quinta avenue.