A quick tip to help you quickly generate flavorful cultures:
Language and culture are deeply embedded in each other, so much so that when we appropriate one for a new race or people in an RPG, we almost automatically grab them both. Take, for example, White Wolf’s original Werewolf game – the nature-mysticism that the werewolves adhered to seemed to be loosely based in Native American beliefs (or cliches about them – I’m not sure), and their naming conventions ended up being similar. We’ve seen plenty of fantasy analogues to real-world regions (Al-Qadim, Rokugan, Maztica, Nyambe) that do this on a larger scale. People even do this unconsciously – consider the Scottish Dwarf Syndrome – or the tendency of many people to use stereotypically English-countryside place names in bucolic areas.
So here is a quick tip based on this observation:
To create a flavorful culture that feels a bit alien in a very short amount of time, grab linguistic conventions from one culture and combine it with the cultural flavor of another (very different) one. You want to have an Ancient Greek analogue in your game, but don’t want it to be too obvious a rip-off? Use place names and linguistic conventions that are, say, of Scandinavian origin. Neither of these are unusual in most fantasy worlds, but the combination is likely to throw off expectations.