Cuba, really. Vinales is worth having on your itinerary, stay away from Varadero, Trinidad is worth it even if it is on everyone's must see list, Cienfuegos is also worth dropping in on your way through.
Do remember, they don't have shops to speak of and for visitors wifi is limited to relatively few (but very busy) public wifi areas. The "take stuff like pencils" for the kiddies is an overworked meme, but has some (small) validity especially if you want to feel like a colonial overlord dispensing largesse. We took some pound shop tat but struggled to find appropriate times to use it - we ended up giving to grandma and the like in the homestays for the grandkids. They don't have a "disposable" culture (yet) which means that things like disposable cutlery, napkins etc are in very short supply. As is bog roll. See the first sentence, you will find it difficult to buy even with your hard currency (the CUC or "kook" as it is referred to).
Travelling through a magnificent country without a single advert in sight is worth it all.
(ETA- as you are going back, not much of that is a surprise. I suspect not that much has changed, except in Havana and Varadero)