Well, drow are already in, but the others would be good.
In terms of what I would really like to see, mainly the ones from older campaigns. So
Thri-Kreen
Mul
Half-Giant (and actually be BIG, not re-skinned goliaths)
Bauriar
Rogue Modron
Warforged
Changeling
Shifter
I know the last three appeared in a UA article, but were pretty weak/bland.
Otherwise kobolds, goblinoids, and lizardfolk would be nice for more cosmopolitan settings where alignment isnt race determined (Eberron, Al-Quadim, etc).