I see it the opposite way. The current crop leaves a lot of 'empty' space on the right (and bottom, now that I think more about it). As a result, it takes attention away from the focus of the image, which is the fog filled, dizzying heights. The tree adds scale which is why it's good to keep it in there, but there's not need to show all of that empty space around it.
By cropping more tightly in toward the tree (both on the right and bottom of the image), it add a lot more tension and allows the focus of the image to fill more of the frame. In essence, it simplifies the image.
The other difficult part about this image is the fact that the cliff face runs along the center vertical of the image. Conventional wisdom says that this is a bad thing and, while I genearally don't like conventional wisdom, I agree with it here. By cropping closer on the right, you take that cliff out of dead center which also helps add depth to the image.
Note: I'm not saying that it's a bad image, just that it could suffer through some improvements.