If you are going to one of the resorts you may not need all the jabs. Anyway try Boots. Some jabs may still be free on the NHS.
I went to Cuba a few years back, and we drove around the island (rather than being whisked to one of the resorts).
If you are doing the same you will either like it or you won't.
It's the sort of place you have to be careful recommending unless you know the person really well. I enjoyed it.
Havana is far safer than the back streets of London. Poverty is rife but the people are friendly but have been badly let down by the regime. And like all socialist utopias there are places where there are very wealthy people.
Cuban 'motorways' were interesting. Just like the day when the Russians quit in the 80s, minimal trafffic, and cows and folks on cycles.
Enjoy.