Well beyond my taste in what Civs they include, how do you even have strengths for Nigeria? It's the same with a lot of these modern countries - sure a lot of people live in them, but at least by reputation their defining characteristic is being poorly run. At least with historical civs there is a certain gloss added by history where we forget the grim reality of some of them (I'm looking at 600-900's Byzantine Empire with this comment).
With countries like Nigeria, Cuba etc., there is a very good chance they won't exist in about 100 years. So at least give them a little bit of time to establish some sort of nationhood.