Light in a room is not a single layer.
The light you need to move around the room is not the light you want when you sit on the sofa. Do not ask one ceiling for both.
WRITING
Does light actually affect our mood?
It does. How much light there is, when it arrives and its colour change how alert you feel. That effect has been measured.
What is ambiance?
Ambiance is how the room feels in that moment. A product that flashes colours on and off is not ambiance. A low, warm wall wash moves toward evening; green and dim recalls the quiet of a forest.