I don't think it was to shoehorn the Horde v Alliance stuff, but rather more of a design choice. Ashenvale is a BIG zone and a contested territory because of the Horde lumber mill from Warcraft 3. There wasn't much of a Horde vs Alliance narrative as much as it was Arch Druid Fandral Staghelm being one of the worst leaders to the Alliance, that he basically took Malfurion's role and had the Night Elves stay in Darnassus because it was all HIS idea.
If you really think about it, everything that people didn't like about the Night Elves going from Warcraft 3 to WoW could all be pointed towards Fandral Staghelm.