I prefer the old fashioned tool boxes. Back in the day, most every mechanic I worked with had pretty much the same setup, and the biggest boxes you saw were usually 36"
I worked in one place where company policy dictated how you should organize your toolbox and the accepted size of that box.
Top Box:
Under the lid -- all the chrome sockets
Lots of shallow small drawers in the top box for all the small parts and precision measuring tools a mechanic accumulates. It was easy to compartmentalize with that kind of setup
Then full-lenth shallow and mid-depth drawers for ratchets and socket accessories, torque wrenches, and specialty tools
Bottom Box:
On the bottom box there were lots of full length shallow drawers for displaying wrenches, screwdrivers, and pliers.
Further down, some full length mid-depth drawers for power tools, hammers, specialty tools, and impact sockets
Way on the bottom; full legth deep drawers for all the testing equipment, analyzers and boxed instruments that go along with the job.

If you were a seasoned vet, chances are you had a side cabinet and an intermediate box full of specialty equipment, homemade tools, and "rare" manuals (only the tall guys went for intermediate boxes)
I just described the the old 70's vintage MAC/MATCO/SNAP-ON and "SEARS Best" 36" chests/cabinets. They were my favorites --