So I've been dreaming about this for a while. I would love to have orc druids.
To me it would be a natural fit, but not because of wow lore.
I played a few table top RPGs in the past, and in one of them there were Orc shape-shifters. They had individual rage animals into which they could transform during combat. They had to get wounded enough to be able to transform, just like Berserkers.
In wow, with their shamanistic side, they are close to wolf spirits, and have a close relationship with their worg companions.
I would love to see them with Wolf/Worg Feral forms along with the orcishly stylized established Guardian and Restoration forms.
The only spec that doesn't really fit is the Balance spec, but it's just class mechanics from there.
I have a feeling that we might get some new class race combos next expansion from the Paladin Class Hall followers.
There are two Nightelf Paladin followers, maybe we'll see some more of that?