About size : Two Octaves
When i play melody on a ribbon, going over two octaves, and making pitch shifts more than two octaves, i some times find useful.
But harmonically, i mean from the ability to make a chord, two octaves has enough space for me to make any chord in any root. You can’t unwrap all the open chord inversions, but an arpeggiator can do that.
One thing i like in microtonal systems, is harmonically being able to bend parts of a chord just a little. To get the pure just tuning. Maybe moving the third around, or sliding two notes and transitioning from one chord to another. Like V to I, or ii to V, etc.
For weaving chords, two octaves would be enough.
I wonder about describing three, or four, or maybe even five notes, of an arpeggiated chord and being able to bend those notes just slightly, and have those bent notes arpeggiate.
The multicolored LEDs above each key, not sure but potentially, the color could feedback information on pitch bend ? Or perhaps the color might reflect on a vertical position change, that also might arpeggiate ?
About size : Finger Drumming
Eight pads, each a different percussive element, particularly if they each had an expressive playing surface, one for each of the four fingers of two hands, would work very well. I notice that the black and white guide stripes below the playing surface make nice sized square playing pads, about the right size.
It might be nice to be able to lay down a pattern, and have that pattern loop.
