Bingowings:
It might add to the already high realism of the matte to add just a tad of haze infront of the palace to blend it in with with the background and further the illusion of depth.

I tried it before but it didn't look right. I'm not sure something that close to the POV would really have much of a haze layer anyway, especially in a scape as deep as this.

I think blending the palace in with the background would have the opposite effect to creating more depth, and it's the one thing in the matte that should look like it's not in the background.

Maybe when I've finished the canyon on the left and removed the rock feature I can tinker with the depth layering but I don't think it needs it at the moment.