A very good idea, even if it mixes situations which are quite different, i.e. Congo (maybe 10% IE (French)-speakers, colonial language) and Armenia (probably 90% IE (Armenian)-speakers, national language), but I guess your idea is to show how widespread IE languages are in some way or other.
A few suggestions:
– Could you accept « Gambia » as well instead of « The Gambia », since you place it under G?
– I also think you should accept « St Lucia », « St Vincent » etc., not only « Saint Lucia »...