“Forest Explore” short animation practice

Forest Explore is a short animation, only a few seconds, is a practice of 'depth'.
As shown above, you can see this animation is composed of three layers, I used dark brown for front layer, light brown for middle, white for the back one. I use these three color because in the forest, during the night or early bird everywhere are dark and hard to see the things, however, the moonlight through the gaps between the branches let we can only see the bright shadow at a distance, and close up there is no light and appear very dark.
In this work, three layers applied with different speed in order to create a 'real world' version, I try to show the audience a kind of 'follow' or 'running' in the forest. In my research, some animation did similar thing, such as:


During this animation, a creature walk in the forest, we can see that background used light/white color to draw trees, and closer part use dark/black color, like shadow. When the creature walking in the forest, background(white trees) moving slower than the front in order to show the distance between the creature and the fathomless forest, it simulate a huge environmental settings (2.5D not 3D).
Above words talk about the color and speed, now I would like to talk about the direction of movement. You might see that creature animation used normal physics principal. When he walked to the right, tree moving to the left(both front and behind), it is always moving in the opposite direction. I did different way,why? My practice name is 'Forest Explore', I have to show the meaning of Explore in my work, is it? what is explore? To search into or travel in for the purpose of discovery: exploring outer space.
Yes, have to travel, walk into a place to finding something, into the forest. When we walk into a place, go ahead we will find, on both sides of the scenery will move back, we go into deeper. So, I tried to make the top two layers moving from one side to another side, (not from middle of screen to the end-side), in order to simulate a 'into' movement. But, it is not fully successful, first, move to fast, audience doesn't understand why the layer moving in this direction; second, subvert the normal cognitive model, usually on both sides of the landscape we see are slowly moving backwards instead of moving from one side to the other side; thirdly, not select right color in this work ( I don't know why, but I just think I should take other colors, maybe black black and white? light/dark brown not make sense....)