I would be in Merida MX, about as far from the vacation beaches as is possible to get, about as close to the middle of the jungles (and heat-humidity-mosquitoes-daily rain storms) as is possible to get.
We used to vacation at Ixtapa back when we lived in Minnesota. Board the airplane at 15 below zero. Three hours later, 85 degrees warm.
We visited Huatulco when there was just one hotel on the beach. Good food. Clean beach but nothing to do otherwise, so we asked the hotel mgr for suggestions.
He got us on a spotless Air Liberdat DC-3 and flew us to Oaxaca city. Very neat, old historic city.
We just missed the Oaxaca radish festival...