So the artstyle will never change, only when someone conquers the city
(you only check the citystyle once, on city conquest, right?)
Then this will look strange after a couple hundred years/turns pass, when your culture takes over the conquered civ's culture
Maybe this modcomp could be expanded
Ideally, all cities artstlye should continually follow the biggest culture in the city
Of course we want to avoid too much python checks, and this would mean checking every city on the map every turn
But what if we reduce the number of turns between checks?
Checking for this every 5-10 turn might be enough, and probably won't slow the game down too much
There may be many other ideas to reduce python checks: save the cities which were already conquered (or maybe flipped) during the game into an array, and only check those
Similar how platyping did in his wonder:
http://forums.civfanatics.com/showpost.php?p=11701335&postcount=1111