Hey Martin this is great!
The only thing that is bothering me, is that the contrast of the edges is too strong to my liking.
Maybe use a Colorramp after your color texture to reduce that…
Your version:
with Colorramp:
With different lighting…your version:
and with Colorramp:
I don’t mean to say: ‘use exactly this Colorramp with these values’ or so, just find a way to reduce the contrast (maybe just a Color > Brightness/Contrast Node…)
But this is only my personal opinion; if you like the contrast, then keep it!
The rocks with their detailing and Normal Maps look absolutely fantastic!