The main player races are Humans, Dwarves, Elves, Drow, Hobbits(yes hobbits, not kender), Gnomes(ok they’re kender but thats copyrighted I’m pretty sure :-P), Grimmians(goblinoids), Sobexyes(lizardmen), and Skuulgard(hobgoblins)
This is an alignment free system/setting, but I may reference it just for simplicity.
Incidentally there are many more half-races, but all are less common, and not generally different enough from the base races to warrant their own description. At the very least none have formed their own society.
Half-humans tend to fill roles members off full-blood races don’t tend towards, I.e. A half-drow would likely become a warrior, or a thief, rather than a mage or cleric like most PC level drow. I think the ideal way to work half-breeds into the system would be through Qualities.