I usually prefer to think in terms of cultural elements instead of cultural styles. For example, I might have a fuedal-steampunk-Aztec campaign.
A feudal culture is likely to arise at certain technological levels. World of Greyhawk, Forgottem Realms, and Medieval Europe are what I would call Classical-Feudal, arising from a mythology like the classical myths of Greece and Rome.
(Although Medieval Europe would be a Monotheistic-Classical-Feudal culture, while WoG and FR do not enter a monotheistic phase. Iron Kingdoms would be Plesio-Monotheistic since most people in a given kingdom will be worshipping one deity.)
My homebrew of Audor is a Nordic Feudal culture, where worship of Asgardian deities continues as they build castles and networks of dukes and barons and lords. Interestingly enough, my homebrew history has a war in which monotheists from the south tried to impose worship of their deity on the north. They failed, and now all who seek to hold an official position must take an oath recognizing the authority of Odin, although they are allowed to worship or not worship any deities they please.
I dislike the term "oriental" but I suppose it is as good as "nordic", where "oriental" means "east" in the same way that "nordic" means "north". It just so happens that usually my oriental cultures end up on the eastern ends of my continents, but that is just a coincidence. Typically I mix and match, putting oriental style elements in with other cultures.
One of the favorite cultures I invented was the Kosaka, which started out as vaguely mongolian-like, but then I started thinking of a wind goddess and how she would influence their culture. They are still nomadic horsemen from the eastern plains (which makes them vaguely scythian-hun-turk-mongolian-like), but they have their own unique culture based on their relations with the gods I invented.
I created another culture, the Nodihoda, by setting a few things sacred to them: water, silver, their alphabet, and the number 5. My intent was to see how far I could go in inventing something truly novel. I never did much with them, but I am also not sure how I would describe them in traditional terms. They turned out to be a little bit like the mesopotamians, perhaps like the Sumarians.
My terminology:
Classical refers to societies based on or derived from Greek/Roman-style basis, often with deities who are fiercely competitive for worshippers.
Feudal refers to societies with elaborate fortresses and levels of nobles with lower ranks owing fealty to upper ranks; each noble is responsible for maintaining security over a given territory.
Nordic refers to societies that worship Asgardian deities or deities like the Asgardians. These pantheons are much more closely knit than the classical pantheons. Also implies a "northern" culture in which warlike raiders fight trolls and giants in the north, or ride longships on expeditions for adventure and treasure. (My Audor setting was a bit land-locked, but the culture of adventurers seeking treasure was woven throughout the society, with tomb-raiding even considered a legal and respectable activity.)
Oriental refers to societies that typically support high population densities, use bright colors in their architecture and clothing, and express great reference for spirits. Silk is often used for clothing, and rice is often used for food. There is typically an emporer who has almost unquestioned authority, even if it is only ceremonial.