Is their any culture you want represented better in particracy, or maybe it isn't represented at all, and you want it to be? Perhaps you can be specific, and point to some culture less rock you would like to implement it in?
Some I'd like to see;
More variations of English speaking cultures - In order to be realistic, we should probably acknowledge that the English language is always going to be dominant. However, this isn't an excuse for blandness. If we acknowledge Luthori as Victorian England, then we should try to limit other English Monarchy cultures. Instead, I'd like to see a Scottish nation, a puritanical King hating Republic (by which I don't mean, "it has a president and a Senate", I thinking more Oliver Cromwell), a Bella South Confederate nation, an Australian, Canadian or New Zealand culture, an American culture that is actually interesting (as in being a well RPd, believable American culture instead of just having "a president and a Senate" and pics of American politicians).
Aryans - By which I mean a Iranian, Persian offshot of the Majatran family tree, to counter balance the Arabs. They could be written in as the ancient rivals of the Artanian Empire, just like the Sassanids and the Parthians were the rivals of the Roman Empire. It would also explain how a supposedly Arab nation once elected a party called the National Bolshevik Aryan Labour Party, and would explain who the fuck those "desert people" Godwin was descended from were.
More variations of Asians/Gao-Showa - This has been going quite well, from being almost universally Japanese, quite a few nations with Gao-Showan populations now have a unique language rather than just being Japanese. We have the Kyo (Koreans) in Drania, the Han in Indrala, and Gao-Showa proper (Japanese) in Sekowo and Hulstria. Kazulia's Gao-Showa would work best as a Hunnic, Mongol culture, which would explain their absence in political life and would fit in better in a snowy Viking country.
Egypt - Ancient Egyptians rock.
More Africans! Seriously, particracy is full of crackers. It must have evolved differently to RL earth or had some terrible genocide's in the unrecorded past.