If Ogres dont make it into the Horde as a playable race, Blizzard is dumber than i thought.
As for the Alliance races i see two possible, Pearlfin Jinyu are ok, but they are linked with the Hozen for the Horde. It would be extremly stupid if Blizzard added playable Hozen before Ogres.
Arakkoa are the more interesting animal/man race. Objectively speaking, the Arakkoa have way more lore than the Jinyu and they bring way more to the table in terms of what a new race could offer the Alliance. Since the Light and the Void are the most important forces in the warcraft universe, the Alliance needs a race with deep knowledge and understanding of the Void if they hope to stand against the darkness that is coming. Horde has the Cult of Forgotten Shadow. Alliance could get Skettis Outcasts(they are already allied with the Naaru) or they could get the AU Order of the Awakened to join.
I personally want to play as a corrupted Arakkoa but i would be fine with the original Arakkoa since they would probably appeal to more players. Blizzard could add corrupted Arakkoa and 2 head Ogres as subraces later on.