I have no problem with taking Cuba over... In a friendly manner anyway... Cuba is a jewel of the Gulf, or should be.
Get the government out of the way and it would become a very prosperous region on tourism alone. A stable, capitalist system based on Yankee bucks would have developers salivating. And many, many Cuban people from the US would flock back to Cuba in a minute.
It would be a matter of years, not decades, and Cuba would be that jewel again.