We don't tend to move the rolling scrap bin much and the items toward the back corner of it are hard to get to, it would be a good candidate for revision.
The tube idea is interesting (though perhaps not ideal with our ceiling style), but I think it would tend to conceal items. I prefer 'observable' storage for non-uniform (scrap) stuff. On a wall short up-down stacks of stuff are ok, but front-to-back is not, because you can't see the stuff in the back. Opposite for overhead.
A combination of overhead hooks for long stuff (keeps stuff visible, out of the way, and spacing between hooks discourages storage of short items), and shallow shelves against a wall for shorter items (visible, out of the way, and solid bottom encourages use for short items) might give us better use of floor space, and better access to see and access the materials. Also it would be fun to watch short people trying to get to the ceiling storage.