this post is probably useless as you realized by yourself what people need here
Instead of having to juggle with instrument ranges XL XXL, note mapping etc… just 3 midi channels are the need of users that would just use normal ranges without having to transpose…
this would give two main advatages, full rhythm section and easy midi file conversion (no editing at all! unsupported channels do not play and standard channels 2,10 and 1/(selectable)? will be read correctly from a standard midi file!), then together with the autoplay function (is it still on the horizon?) you will have a very powerful accompanying tool!