Well for me the Problems with Teldrassil are these:
- It is disconnected from the Kalimdor mainland and there for from the forest they had a connection to for 10k years also they basically are exposed there in the ocean
- It moves them away from their home Ashenvale
- The tree is just too peaceful... and just does not fit their savage WC3 theme
- I question if night elfs should have a town at all I just don't think they would like to live in there
Night elfs should just have some losly connected villages/communities and some ancient buildings/structures around them. But I would even the Eldre'Thalas as an improvement over Teldrassil, its at least well integrated into the enviroment just like the temple in Feralas.