After reading the description, I was able to focus on the parts of the art that I assume are the main focus. And based on that, I have to say that I like the majority of the background. I like the look it was given by the painting technique you used, mainly the grass on the hill Luna is standing on and the water in the waterfall. The tress look pretty good too, but they don't look as good as the other things I mentioned. They all kind of look like the same tree in a different place with some minor differences in the details. My only other complaint is that the way the hill is presented. It took me a minute to see that we were looking at a side view of the hill and I think the reason why is because the hill Luna is standing on is just as dark as land below it on the right corner of the picture and because of that, there doesn't seem to be any depth in the hill to show that we are looking at it's side. Other than that, I like the techniques used in this experiment and think that if you continue to use them they will continuously look better.
Hmm... that thing hanging from the tip of the cliff, what is it? Is it water, is it snow, is it ice? Can't quite make it out. Anyway, I like the sense you have created here. Luna is quite cool standing like that. And that's a nice look of that forest that almost feels ethereal. Have you copied any of the trees or have you drawn them all? Also, I have to say that I like this cliff you used. I hope you'll use it more. Well done!