If you hold the camera closer to the ground, of course you miss some of the view of the slope but wouldn't this give a better perspective of how steep a hill would be on a photograph. I don't know, its why I'm asking you scott because you know about these things. I have seen how photos do this (remove perspective). I guess there's many variables in taking good pics and no magic pill for my question.
The only way I know of to convey the steepness of a slope is to shoot across it from the sides, or have things that you can use for scale. Here are a few examples,
Shooting up the slope usually gives a better sense of steepness than shooting down the slope. For instance,
Looking down...
Looking up the exact same spot...
and another shooting up/down example,
Looking down
Looking up
Another looking down
and looking back up just a short part of it
Here is an example of shooting across, note the rider upper right and the vehicle lower left
and another
Make use of human scale where possible
Same shot as above, but zoomed in to show the human...
(center about 1/3 from top)
If you have them, trees can help because they
usually grow vertically, so seeing the angle between the trees and the ground can create a visual reference.
Or the oft ubiquitous power line poles
(note rider about half way up the hill under power lines)
Scale and perspective again,
Having people really helps with the looking down shots because we can relate to the scale of the people
This one has two good clues, the horizon far left and the power lines running up the slope