Format-wise, you have room to put E in a block between A and I. Then you don't have to scroll down, and it's organized more symmetrically.
So São Tomé and Principe, El Salvador, and Costa Rica just... don't exist?
A country's name is what they decide it to be and if they've decided that their name is El Salvador and not The Savior or Timor-Leste and not East Timor, then they're right.
The United States of America, for instance, has decided that its name is a collection of nouns rather than a proper noun itself, so it does change with language. But my name would be Jared whether I'm telling it to you in English, Icelandic, or otherwise. The same is true for Timor-Leste.
It's literally the official name adopted by the UN, EU, and the national standards organisations for the US, UK, France, Germany, and Sweden, and the CIA World Factbook. The fact that everything on jetpunk uses the Countries of the World Quiz is convenient for the cohesiveness of the site, but it still stands that even the original quiz is flawed.