> which key do you think is the easiest to play on piano?
Sorry, "easiest" may not be the best word. C major is THE key of the piano keyboard and playing in C major is so easy because all of the non-exotic chords (sorry, I don't know the english nomenclature) are played on the same kind of keys and they have identical, predictable shapes.
On a keyboard like Dodeka, all chords in all keys have predictable shapes, because why shouldn't they? You should be able to transpose any song by simply moving your hands a little to the side, anything else is just bad UI.
Sorry, "easiest" may not be the best word. C major is THE key of the piano keyboard and playing in C major is so easy because all of the non-exotic chords (sorry, I don't know the english nomenclature) are played on the same kind of keys and they have identical, predictable shapes.
On a keyboard like Dodeka, all chords in all keys have predictable shapes, because why shouldn't they? You should be able to transpose any song by simply moving your hands a little to the side, anything else is just bad UI.