I like the 3D visualization at http://binwalk.org/wp-content/uploads/2013/12/avr32_3d.gif
What might perhaps also be interesting, is to create a plugin for binwalk that compares the firmware with other firmware binaries.
As someone who has looked through many different types of files in doing quite a bit of RE, I've become able to separate out different types of data just by the "feel" of how it looks in a text editor; Z80 and 6502 code, x86, MIPS, ARM, bitmap images, and compressed data all have different "textures" to them.
It is very useful. As different file types and data structures. Often has a quite common entropy level to them.
Rather than doing it in your head as you do one can use a machine to help, which happens to be the hole point of machines.
It is just bytes visually represented. 1byte = x axis, 2byte = y axis, 3byte = z axis. And then jump forward and repeat.