Honesly, Race is simply a look thing. Every class starts with different starting abilities and strengths, however end game gear will ballance all of this out. So play what you want to play, and enjoy the game however you want to do it.
Example:
I have an Iksar Shadow Knight, High Elf Assassin, Orge Guardian, Wood Elf Berserker, Erudite Coercer, Karren Defiler, ect.