Alliance have a thread running on their allied races, so why not a counterpart for the Horde ones?
Over the years, the main servers that I play on have become faction imbalanced and lean heavily Alliance. I still have Horde characters and I'm slowly leveling a HMT Shaman, but for Nightborne I went Combat Rogue.
If you're leveling a Horde allied race, what did you go with and how do you like it?