What a great improvement already!
I see you've changed the lighting, but it is still from the back, though a bit more from the side indeed, but still way too much. I'd move it for another -50 degrees or so.
For now I would forget about the stones, keep it for later.
First you could do some other things
A strong point now is the focal point and buildup of depth. The viewer is now more drawn into the image.
The clouds give very nice sense of scale and to even further improve it I suggest you reduce the scales of your bushes and trees by half.
Also, do you use size variations for your populations? I strongly recommonded using that because it makes it more realistic.
To add size variation double-click on your population-node and go the third tab "object scale".
At default these are set to 1 for min. and max. scale.
So, to explain what I suggest we assume yours is set to the default of 1 for min. and max.
First, let's decrease the scale of object by half. So set min. and max. scale to 0.5
But, to add size variation you need to alter one of the two, so I suggest you enter 0.25 for min. and 0.5 for max.
I find a ratio of 1:2 or 1:3 best often.
Consequently you will need to increase the density of your populations.
I think the coverage for your bushes is fine, so if you're going to decrease the size of the bushes then increase the density to get a similar coverage.
In general some more trees could be nice. Maybe some more clumps too.
This may sound like a lot to do, but in fact it is just a dozen of minutes of work.
Reduce scales, add size variation and increase densities. Then move the sun more to the right and start testing!
After you've settled this you can start focussing on your stones again
Good luck!
Martin
