Seeds?
I agree with the other posters. Unless you want to kill yourself agonizing over details and reinventing the wheel, you should base your cultures on existing or historical real world cultures. Don't worry at all about being accurate; just go with gross generalities and stereotypes and run with it.
Also, remember that Cha represents self-awareness. So, high Cha races will tend to be selfish, low Cha races will tend to be more communist.
Svirfneblin: Vietnamese, as depicted in movies like Platoon. Sneaky, fight with guerilla tactics. Untrustworthy, willing to sacrifice individual soldiers for the greater good. (6 Cha).
Derro: Cold-war Russian communist, as depicted in Bond films. Cold, brutal, don't value individuals or freedom.
Duergar: Old-school conquistador Spanish, complete with Inquisition, greed, and genocidal urges. These guys would take great pride in Duergar culture, but not so much pride in themselves as individuals. Think of your typical goofball sports superfan who paints his body and says "We won last night's game" instead of "The Yankees won last night's game"--it's all about the race, not about the individual.
Illithid: Instead of the lazy, cowardly creatures in FR, I'd depict these things as truly alien. Reject human motivations like wealth and political power, and come up with something more unusual. Like... maybe the feed not only on brain, but also the emotions fear, agony, and despair. So, they plot to increase the world's output of these emotions, while protecting their own existence. They view the intelligent races as we view an individual crop plant: the plant contributes to the world's supply of oxygen and food, and that's great, but the value of an individual stalk of corn is zero.
Kobold: Voodoo tribal culture. Fear-based culture; it's all about appeasing or hiding from whatever it is that threatens you.
Beholder: Another alien culture. Beholders don't wear clothes or use tools, they don't manufacture anything. They can tunnel with Disintegrate and move stuff with Telekinesis. But they have high Wis, Int, and Cha--they're very aware creatures. Maybe you could run with the function of their main eye. Make Beholders have a hatred for magic, and a passion for destroying magic items. They jockey for personal reputation and social power, earning social cred by destroying magic items and those who wield them. I'd definitely portray Beholders as haughty. They'd view other races as you and I view ants: sure, ants are alive, and can react to stimuli and use tools and build structures and communicate with each other, but they're not really intelligent. I think Beholders would view the other race's reliance on magic as a gross weakness, and would delight in showing the other races how pitiful they are once their little toys are rendered harmless under the Beholder's gaze.
-z
