When entering buildings it still sounds like you're outside.
There is no sense of being inside something, away from the elements.
You can still clearly hear the same outdoor samples like the wind, insects etc...
There needs to be more deadening or resonance of the acoustics depending on the size of the building and the material that It is made from.
Also all the buildings are filled with visible swarms of butterflies, bees, crickets... etc
Something as simple as this could make a MASSIVE difference... http://youtu.be/ptBm0YDKne8