Currently with the Temple of POWERBALL I've won 90% as ally. Only losses is when people in greens and not even crafted pvp wander in on our side and blizzard just happened to pick a horde premade for that game.
EoTS is similar for me, AV and IOC are bloodbaths with alliance loling their way to the final boss. The only ones where alliance truly struggles are CTF and capture and holds (and that stupid TF2 ripoff one that no alliance member seems to know how to play), which is funny because when they are combined into EOTS alliance does great...