No clue how hard this would be, but unique racial abilities, that in the future could possibly be stolen (From what i've read in the description) would be neat.
Like vampires getting buffs from blood-saturation, and maybe liches being able to raise undead from souls they eat.That's all really, fun game, I don't know how to progress past level 2, but it reminds me of a fantasy cog-mind, but in alpha.