There's already some improvement, but not yet what I had in mind:
Perhaps it's better to stretch the fractals even further. I usually use at least 10 for both X and Z.
It's "best" to apply it to the steeper surfaces, I'm not sure how you've restricted them at the moment.
The scales are quite big, I'd use very small scales and less scale variation.
I have scales in mind like I the ones I've drawn in the image.
It's probably easiest to let the preview finish and measure the desired scale and apply it to your stretched powerfractal.
So if you find a size of 10m then make the powerfractal scales like: 10m feature, 25 large and 1 or 2m small scale.
Also, make it quite contrasted to get sharp profiles.
Don't forget to break up the powerfractal for variation.
Hope some of this will help further.
Martin
