It might be worth noting that the Haitian revolution bears a closer resemblance to its French predecessor than to the American version.

Back in high school I took a history class titled "History of the Americas." It tracked the development of the United States, Latin American and Canada by section, chronologically. Our teacher concluded that, generally speaking, the three main ingredients for a successful democracy are literacy, a broad middle class and experience in self-government. All three ingredients were present in the English/American colonies but were not in the Spanish colonies. We did not cover the development of the Caribbean nations, but a quick overview shows that, even with their problems, the colonies that were controlled by England generally are better off than their Spanish and French counterparts.