Haha, also Sylvanas could have survived, remenber that she had more Valkyrs, so she could have been rezzed after that :P
And i'm not pretty sure that the Goblins would become neutral once again, they could also join with the Dwarves and Gnomes, also... why should it be like Starcraft? it can be something different (it can be the same type of gameplay like WC3 but not the that the factions works like SC