I hope you don't mind that I played a bit with this photo.
I tried enhancing that lighting that I liked. So, in Photoshop I
Increased contrast +16
Sharpened (Since it was lacking in sharpness)
Adjust levels a bit to bring out the light vs. dark
And just did a final unsharp mask at 20%
First I played with layers a bit, making it brighter. Then I created a duplicate layer to make a gradient running from the top right to lower left. Overlaid the gradient with 40 per cent transparency and ended up with this. Hope you like it.