Your source for geographic locations of countries might be contentious especially for countries that are within multiple regions, and your developing / developed status is definitely so. I would love to see your data sources on that.
Consider using direct sources like the CIA World Factbook instead of Wikipedia. I took a cursory look at your data and I’ve spotted a few inaccuracies fairly quickly. Getting basic facts wrong about a country doesn’t inspire confidence about the freshness of the visa information.
