Jesse

The Alliance and Horde quests were designed with wholly different themes in mind. So far on Alliance I'm pretty sure the basic theme is "Player X is special." or "Player X is thee Hero.". The Draenei starting area shows off this especially well with the Furbolg language quest line and the subsequent way all the Furbolgs will respond to your character. The final quest in the area adds to the theme with a personal thank you from Velen, the racial leader of the Draenei. The Horde on the other hand have a "Player X makes the Horde proud." or "Player X has contributed to the cause." theme to their quests. I also noticed in my research that the Alliance has twice as many group quests under level 25. Then there is the Alliance-only Sprite Darter non-combat pet. In the long run none of this matters and everything from Outland onwards is pretty much exactly the same, but in the lower leveling range the Alliance does tend to boost your self-esteem more.