I’m personally not a fan of all the added blue to the greys. The increase of contrast in the highlights look like they rob the image of fine detail quality for the sake of adding more light. Having been to the dunes many times, I don’t really ever remember the sky being so vibrantly blue, though I’m sure atmospherics would be different on other worlds and locations. I think JJ nailed the sand look with Jakku personally https://www.youtube.com/watch?v=8sarFZJl3h0&ab_channel=JohnnyJawbone