Who are you?

Elves and dwarves have become boring. After seventy some years of Tolkien-esque dwarves and elves these races have become bland and over-used to fans of fantasy fiction. So we need new races. Races we haven’t seen before than can make role-playing feel new and exciting again.

However, as has been remarked, this can make your average adventuring party seem like the cantina from Star Wars. 

I wouldn’t say new races are a bad idea, but they certainly need to be established: you can’t just drop an entire species into a campaign world. They need to feel like they belong. And moderation is also good. A couple new races are special but a half-dozen begin to crowd things.