Hi I've twice to Cuba and got married there.
It is a amazing country - unlike others here we did the 5Star AI but we did explore as well.
We stayed in Holguin so as someone has said it's the opposite end to Havana and they had stopped the flights to Havana at the time so unless you want to do a very very long drive it wasn't possible.
Cuba is not a developed country so you do need to be prepared for that, there's no shopping malls, or strips of bars/restaurants you would see in other places. My Dad forgot his dress shirt for the wedding ( don't get me started) and we ended up borrowing a shirt from our rep as there are no shops. People are very poor but the nicest you will ever meet.
Our hotel was amazing, and unusal for Cuba food was great, tons of choice, we had 6 al carte resturntants, 24 hour food/drink, tons of activites etc. Yes the food in cuba can be limited, everything is imported so you wouldn't see 'normal' brands, but there is always something to eat. Personally we did not tip every person we met, you don't need too, it's a personal choice. We did, as others tend to do, leave clothing, medication etc as these are things they struggle to get.
5 star there is not like 5 star in mexico etc and that is reflective in the price. You'll pay double in Mexico for 5 star.
Personally I love Cuba and found it a relaxing & beautiful place. Make sure you leave your hotel, we did some village tours, dolphins, horse riding, fishing, boat trip etc and they were amazing. Enjoy