This is what I did with mine!
The right side has no waterfalls or anything but instead there is a space between the plaza and the cliff where I put a bench, a log stool, and some other bushes. The second and third layer have pine trees and bushes lining all the way around. I think it looks very nice because there are waterfalls, but they're not super over the top if that makes sense! Of course there is also nothing wrong with lots of waterfalls too if that's your thing!
I hope this helps. c:
View attachment 272229