Could you do like 2 layers of wire mesh? One open and a little thicker with bigger openings on the outside in a painted color of your choice (a little easier on the eyes) and then get some fine wire mesh for the inside layer, which will almost be invisible to the eye, but will protect from rocks etc?
http://www.bwire.com/
Say like using this site, a 5 x 5 mesh on the outside or maybe 4 x 4 and then something like a 20 x 20 or 30 x 30 mesh underneath that layer to do the dirty work.
Just a thought here, would this look good? work?