Nice! For onions, definitely. For potatoes I'm not so sure, since they would tend to dry out if fully exposed to air, and would turn green (poisonous) if exposed to light.
Potatoes
DO store well in mesh bags as long as you keep them in the dark. I have never had any problem with potatoes drying when stored in a mesh bag. As a matter of fact I have had potatoes stored in a closed container spoil because of too much moisture.
I always collect twine and rope scraps when I go to the seaside. Those scraps have come in useful many times. Cheers. Tony