who gives a flying fuck about expansions being horde and alliance favored. wrath was alliance, cataclysm was dog shit, vanilla was a conglomerate, TBC was blood elves and burning legion. i dont honestly care about shit being horde or alliance centric.
i feel that the horde should kill garrosh quite simply because it is their problem. garrosh ousted his own faction and shall suffer for it.
the alliance just see it as a weak moment to strike at the horde, they truly dont care who is the warchief as long as the horde is destroyed or subjugated.