If you want to go a step further and separate your tools, you'll need to get a bit more creative. One way is to utilize PVC pipe to make containers for your tools by attaching to two pieces of wood and hanging that from the wall. Another solution is to utilize a pegboard for your larger items as well, as they can hang from hooks similarly to smaller items.
Due to their susceptibility to rust, steel storage units should be avoided. Among metal storage units, rust-free aluminum is usually the most sensible choice in siding. Metal siding is hardly the most visually appealing choice.