The story does not need to be drek. It could be very inspirational and truly telling. At this point the Alliance/ Horde conflict is an inherited race war. It made some sense 20 years ago. Now... not so much. The PC's should be the driving force of this change. "We" have fought side by side during these conflicts. The bond of brothers in arms should start to prevail over the archaic politics of our leaders. Almost every racial leader knows and respects at least one of the leaders on the other side.
What I truly hope to see next expansion... tie up Old Gods, South Seas, Azshara, Lich King/ Scourge. During which the hold outs for peace (Sylvanas, Genn, Jaina) are either killed or have a change of heart. The following expansion I want a healing/ rebuilding expansion. During which the world is phased for high level play and you work across previous faction lines to offer aid. You (the PC) have been an adventure, a general conscript, a class leader wielding artifacts of incredible power, are now rebuilding the world. You could see it as being a mercenary or returning to the life as an adventurer. Though the other side may have heard of some of your deeds they do not know the breadth of your ability or compassion to aid those in need.
Now subduing Quillboars or Centaurs or Pygmies may seem like a step backwards but during these phased rebuilding events we could learn of other civilizations. Maybe other catastrophes that happened ages ago. More tomb delving like in Uldum... or archaeological discoveries. Or with the Sarganite Keystone we could even start helping rebuild other worlds. The possibilities could be endless.
Just a thought