Hi,
I tried to represent players by a spot, each of them looking to the other side of the board 
I used a total of 3 light sources. The last one is the global lighting: a neon light with a yellow-ish hue located above the board .
Here it comes:
Some tweaks in the material properties of the chessboard have been made to lessen the reflection in the first panel.
The white player is currently thinking hence the stronger light. (Waiting for a black player ?)
And here is the disposition of the lights:
As you can see, for the neon light (Lamp Top), I used an area lighting with a rectangle shape.
It was fun to play with the lights and it might not be the lighting for the final scene, I have yet to try some more dispositions but I am happy with this one 
.
Cheers !