Post 1
What do you mean by variation in cliffs? Different cliff colours/types for different climates?
Sounds like you're putting
tonnes of new textures, I assumed it was only a re-polish of existing textures. Astonishing how nice an old game can look.
Each climate has it's own hi-resolution cliff textures that simulate depth. It looks hi-poly but actually it's not.
Post 2
I just made some screenshot of the nile delta just after sunset:
And here's a little sneak peek of the new rivers:
https://youtu.be/5rhT6ZLInqc