Went 5 years ago. Absolutely amazing, toured around a lot of the west side of the island. Havana, Sancta Clara (Che Guevara Mausoleum is a must visit), Cifeuegos, Trinidad. We finished off with 3 days all inclusive in Cayo Coco. We asked our host to help us arrange transport from Trinidad to Cayo Coco, shared a car with 2 Italian tourists. The driver was crazy, filling up with diesel on a farm, using the top half of a cola bottle to funnel the fuel into the tank while a cigarette was hanging out of his mouth. We got out of the car immediately (with passports) while it happened.
Havana - Ernest Hemingway's hotel is https://www.hotelambosmundoshabana.com/ grand piano playing in the bar with not too expensive Mojitos.
Don't think about car hire, no GPS coverage, poor road signage (in Spanish) and poor road conditions. We used https://viazul.wetransp.com/ air-con coaches for going between towns.
The people are extremely friendly but extremely poor - we took a load of things as the locals can't get many, many things and we gave them to the locals, £1 specs, jet bouncy balls, bras (yes!), football jerseys, toothpaste, deodorant, pens, pencils, chalks etc. Took a few bottles of shower gel, and left them there for the hosts. Our luggage weighed less coming back than going.
Go the local pharmacy to get mosquito repellent - you will need it and not regret the purchase.
Take a look at this - http://www.casaparticularcuba.org/ - you stay with Cuban families, own room and generally own bathroom. You can also pay extra and eat with them.
Send me a PM if you want to know more.