That really is my biggest issue with changing costumes, though, even more than the resource investment or the potential for immaturity. Why is Westernization inevitable? If Shaka is leading the culture game, why isn't everyone else wearing hide kilts? If Genghis Khan is leading the culture game, why isn't everyone else wearing deel? If Russia is leading the culture game, why isn't everyone else wearing cherkeski? On the one hand, everyone in suits shows a lack of imagination; on the other hand, Neo-Nazi Joan of Arc reminds me that I don't trust Firaxis' imagination...
More heirs also means more risk of wars of succession. You have to find a way to deal with unwanted heirs, like the Ottoman policy of state-sponsored fratricide or the European practice of sending extra heirs into the Church. (And then when things go unexpectedly you get Louis IX...)
I loved Punk Joan of Arc. Now you are making me sad. Lol.