Here is the new music layout that I am pushing with CHORDiUM. As you can see, it's actually based on a root-hexagonal layout, although I believe no other hexagonal music layout has done it quite like this. If anyone knows better, do let me know!
The centre of the hexagonal grid is the "1". Musically called the root, and in Scoreless Music, called appropriately the "centre". Every other tone radiates outwards from it.
The right side of the hex corresponds to the "2-3-4" rise. The left side to the "5-6-7" rise.
Music is all about motion, and Scoreless Music has very strong philosophies regarding spatial alignment of physical keys with musical movement. Thus, going "upwards" in music (scale) corresponds to physically moving fingers upwards.
"4" is deliberately placed at the top and "5" at the bottom because in Scoreless Music, "4" is associated with upward movement and "5" is associated with downward movement. The "Up" shape in Scoreless Music is a variant of "4" and the "Down" shape a variant of "5".
The 5 "exceptions" are placed physically adjacent to their most appropriate neighbours.
There are actually very fascinating consequences to this hexagonal layout. More on the math of it when I have time to document it all.