Presumably he'll eventually come back around to clear things up himself, but...
I'm pretty sure what Salmoneous was talking about was the diagonal pattern, not the gradient (which is awesome, btw). Specifically, while the alternating diagonal lines and boxes work fine for the squared-off
foreground blocks, they clash with the shadows and natural shapes of the chimneys and mesas in the background.
I have to agree that the abstract pattern makes those great badlands landforms look two-dimensional and fake, like scenery at a small theatre. Plus, having the pattern be identical between the foreground and background blocks destroys the illusion of depth there would be otherwise; those huge weathered stone outcrops have to be a good ways away to appear only a few blocks wide, yet the pattern is suggesting they're almost close enough for Juni to touch.
Or I could be way off base, missing Salmoneous's point entirely, and just generally wrong.
But my advice is to keep the shadows on the background tiles, and remove the geometric pattern.
(And keep that gradient just as it is! Holy copypasta is it gorgeous.)