Look at Apollo 17 mission pictures (which are interesting as they are set in the most altimetric diverse location of all Apollo landings) and try to asses the distance of features. Afterwards, get the EVA maps and see the actual distances... you will be shocked.

Without atmospheric absorbtion and haze, it is next to impossible to gauge distances.

I think that the main problem of your terrain is the relative scale between horizontal distances and vertical ones. For example, largest "canyon" known is Valles Marineris. It is difficult to get the feeling of its size: in this page http://www.lpi.usra.edu/science/treiman/greatdesert/workshop/poster1/index.html there is a comparison between Valles Marineris and the Grand Canyon, which will give you hard data.

Another problem are shadows: without atmosphere, either you get direct light or the reflected light from nearby cliffs: the actual intensity of the effect depends upon the color of the ground.
Demented conspiracy theories apart, the general lighting of Apollo photographs is so harsh to make the brightest noon on earth look dim by comparison so you are dealing with an enourmous dynamic range (why are some items visible also in shadows? because they are dimly lit by nearby objects and  not so nearby hills).

Bye!!!

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