My Alesis drum kit, Songbook Pro on my iPad, my other guitar player's Kemper Profiler and my keyboardist's Roland keyboard all use midi. None of them use a binary base for their organization. The drum kit can store 70 kits, and other e-drum models have all sorts of different numbers of stored presets. The Profiler stores 625 rigs. SBP doesn't list a song limit, so I suspect that's a single storage size limit rather than a set number of songs. The Roland Keyboard organization appears to be random.
Binary and hex are typically used for under the hood parts of a computer, not user interface. Again, I don't know what the Helix Developers had in mind, so it's a toss up.
ETA: The HX Stomp uses midi. It has 42 banks with A, B, C presets for 3 foot switches. I'm gonna go out on a limb and conclude once and for all that the footswitch number determined the bank organization.