Not sure you should expect that to change. Very few of the minor countries would realistically be able to match up with one of the great nations in the timespan in question.
On another note, The Sims 3 is priced very sympathetically. (I know, it's a guilty pleasure of mine). It's NA only, unfortunately, but buying the entire series on Impulse costs roughly the same as buying one of the expansions on EA Store.
Did I mention I really detest EA store? No? Well, I do.