Best place to have a relaxing holiday in Cuba?

Question

My husband and I are planning to have an all-inclusive holiday in Cuba in the next 3 weeks. It's our first time so we need some advices. Where is the best place to have a relaxing time? We're not planning on touring around just spending a lot of time in the beach. Is Caya Coco or Holguin a good place? What about Varadero?

Thanks a lot in advance for your replies.