I have begun work on a vignette/small diorama which will feature a larger piece of exposed and eroded rock from the Black Hills (Rocky Raccoon will not be present, however!) The overall height is about 4 inches/11 cm from the base. The exposed part will be the focus and have a small waterfall. I know what I want to do here. The sides and back are essentially cut-aways into the side of the rock formation and in my image of the real lilfe site, would not be seen. In the foreground will be a small stream and its bank.
I'm wondering if I should continue the striations I wil have on the front around the side and back or would that look too much like a single piece of rock jutting out of the ground?

Would the water coming from the back negate this effect?

Would I be better to paint the sides black or solid gray?