Yudishtira
Spiritual/Creative
So if we assume we have 10 big and competetive civilizations, you'd have 30 cultures in each of them. I think that's a lot and completely devaluates cultures. Your first 3 cultures might be interesting to get, but after that it's just another culture wonder.
Large countries accumulate a lot of cultures. Look at the US (all of its native cultures), Russia (Sami etc., Siberian, Yakut/Irkut etc.), China (Uighur, disputedly Tibetan, Hongkongese and all its historic cultures including regional ones like Manchu, Szechuan etc.), India and Indonesia. That is as it should be.
As an aside, lots of countries share cultures as well, so it's a shame that is not represented in the mod currently. Maybe someday.....