Agree with Max. I want to exapand it further.
Mexican caribean is beautiful. I had been there almost every year last 5 years. Cozumel is perfect for diving, but isla mujeres is also marvelous and is not far away. Plus the night life of Cancun, and the peacefull resosrts of riviera maya. Everything on close range, excellent service, professional quality, excelent mexican seafood, the opportunity to visit Chichen Itza.