Although this piece is technically astounding and very beautiful to look at, there are a couple of things that bother me - sorry for speaking this late
The first thing is the rocks on the borders: what are those? Rock plates? Even if they make for a nice change, they make little sense to me as they look unnatural and weak. Moreover, the upper side of the rocks on the front borders is not matched by that on the back border neither in shape, nor in arrangement.
The other thing is that the bottom part of the small platform does not read quite right because of the colors, that somehow almost seem to put it somewhere between the background and the foreground.