Lighting: No light coming in from the window but there appears to be a light source inside the room casting light in the lower left. what is casting that light? If we can't see it then it makes it feel a bit off.
Also, might want to throw an image outside that window. Just put a photo on a plane and place it behind the open window. Will make loads of difference.
Professor of Digital Arts
Digital Media Arts College
Boca Raton, Florida