Nice shot, fantastic location. My monitor is not well calibrated, but it does look a little dark to me. If you could open up some of the shadows on the left side of the frame, I think it would improve it.
I like the dark area as is. My eye goes to the lightest area first, the shaft of light. A normal reaction, the eye is usually drawn to the lightest area of a scene first, follows it down to the patch of illuminated water and lingers there to explore the area around the water.
Tom From Beautiful Smith Mountain Lake in Virginia