I am calling them done, even though they are not exactly the way I originally envisioned them. One of the most fascinating aspect of karsts formations are the gnarly trees, hanging on for dear life on the eroded substrate. Unfortunately I tried several approaches and couldn't get it right. So bare karsts it is! I also tried several ways to represent the shimmering water, but they didn't work out either.
What did work out was the bright red raft - looks really cool against the monochromatic scheme.
As opposed to the subdued raft, which looks subdued.
I found some leaf skeletons from the yard and brushed them with gel medium, and stitched them onto the left karst. I think they look fine.
I will review them tomorrow and hopefully they will still look ok. Now onto the research paper...