Havana is quite the place. We got in tow with this local guy who showed us around the back streets and it was an eye opener. On more than one occasion I thought we were going to never be seen again but it was all good. Gave the guy some dollars at the end for his impromptu tour and took him for a few drinks, he was delighted.
Varadero is just tourism but the journey there from Havana is good. We did some farm and river excursions so made a day of it.
I reckon Costa Rica shades it though. 3 days inland in the cloud forest and Mount Arenal touring about. Then 10 days in Guanacaste on pacific coast chilling by the pool, zip lining. Pura Vida as the locals say.