Im currently playing a sham/warr duo, went arms/resto for specs 1-60 which I regret, if I were to do it again id go Fury/Enhance to maximize DPS.

Of course the greatest obstacle will be the fact that double melee can be a pain, due to positioning and LOS issues for combat. Its sometimes easily resolved by taking a step back or turning etc but other times the slave just doesnt want to get LOS on the mob haha. Those two classes can qualify for your race desires, different classes also bring a bit of trouble but hey its more fun!

Race/Class combos for you

Shaman/Rogue
Pally/Pally
Pally/Warrior
Sham/Warr

You already have a hunter/mage so it sort of limits the Draenei to Warr/Sham/Pally
Humans can be anything so decide what youd like the draenei to be and go from there IMO