I think each race can be boiled down to a "default" basic race and then be expanded into different sub-races. Fantasy Craft had a good concept for this with Species feats being used to create sub-species.
Example - Ef
The base elf focuses on the core of the species, which in this case is their longevity, unearthly beauty, senses, and grace - but also their more frail physical form. Due to their longevity they gain increased WIS but are also more aloof (penalties to certain skills). Due to their grace and beauty they are faster than humans, and gain a bonus with certain appearance based skills. They also have keen sight and hearing, but suffer a penalty to CON and don't heal as easily.
Some example Sub-Species are Wood Elves, Gray Elves, and Dark Elves. For instance Wood Elves gain bonuses to tracking, improved DEX, bonuses with stealth and survival, but also suffer a penalty to INT due to lack of more formal education as other elves.