This looks very nice Dave!
I'd like to share some ideas/tips with you if you don't mind:
The rock on the right looks really good and the distorted strata-like structures look really good but are a bit too sharp and too displaced.
Perhaps slightly lowering the displacement and decreasing the contrast of the powerfractal (and/or increasing offset) will make them look a little bit more natural.
A way to create wet looking mud is to use a noise stretched powerfractal with low roughness and contrast to get some smooth wavy look.
The wet look can easily be achieved by adding a default shader as a child layer. The default shader has a specularity setting. Just play with it. I suggest you start with something like specularity 0.1 and roughness 0.2. Specularity = intensity/strength, roughness = spread (less spread is more intensity and vice versa). Don't forget to set the default shader to your desired surface color. Of course you can use powerfractals as input for the color function of the default shader.
Using a default shader you can also do the same for the fake stones. To give them a wet look for example and to displace them to get cool shapes.
So far some of my ideas....just thinking 'loud'
Keep up the good work, you're progressing rapidly!
Martin
