a few rendering tips

1. always adjust camera angle and focal length for a better interior view

2. increasing the luminosity brings the amount of white down - this is under render output - if you are trying to do a luminous or night time type rendering.

3. set indirect bounces up to 2 or 3 and up the ambient intensity

4. if you want an area light to project from all over the polygon and not just the center of the area light you should turn off simple shading and increase the sample level to 256 or so.

5. if you want to soften the shadows increase the spread angle.