Well, I've turned the evil factor on the Dark Elves down a notch... or rather, turned up the sympathetic factor. They're basically just hedonists that have turned to demon-worship, mainly as a rebellion against their stoic, cast-based High-Elven cousins.
The High Elves turned out to be a cross between Vulcans and Githyanki (strange combination, I know) in that they strive to suppress emotions and nonconformity, and they're extremely racist and expansionistic.
Dwarves are very much akin to the post-Viking Age Scandinavian cultures- barbarians pretending to be kings, who have only recently chosen the path of trade over war.
Orcs are like any other hunter-gatherer culture whose entire subsistence is based around large herbivores. Each tribe has its own customs, and none are inherently evil, a lot like the orcs of Eberron.
Gnomes are akin to Eberron's as well, with a few personal tweaks. They've invented many useful things- spectacles, clockwork, magnetic compasses, golem submarines- but they're keeping their secrets secret.
I'm thinking about leaving halflings out altogether, but if I use them they'll probably be analogues to the Roma.
Kobolds are a pest in every major city. They eat rotten food and live in refuse pits, placing value on the trash of other races.
That was a brief rundown, but it's pretty much where I'm at now.