Good luck with your planning and your retirement. Before deciding to go to the Caribbean you need to do a lot more research and probably should think about going for a winter season to see how you like it. I will start you off with a few things to consider.
There is the whole question of hurricane season - roughly June to October. Most, but certainly not all, cruisers try to out of the Caribbean for this time (it is also very hot). People tend to go at least as far south as Grenada and many will have their boats hauled and return to their home countries for several months.
There are fascinating cultural differences to enjoy with islands having English, French, Spanish, and Dutch backgrounds. In the Eastern Caribbean most islands are a daysail apart.
Some cruisers move around a lot while others stay put, you will discover which you are.
We are monohull sailors but could see the advantages of a cat for Caribbean cruising/living.
When thinking about getting to the Caribbean and moving around while there it is all about wind direction. The trades will be both your best friend and worst enemy.
In South Africa doing lots of boat stuff. Departure north from Cape Town around December 15th. Arrival in the Caribbean around the beginning of February, after 5300 miles or so.