MOTM

>c) I understand that people change the scale via CV all the time. But, and
>this is an important thing to consider, is it changed *precisely*? Or do
>people "just want it to change" every so often, and not care *exactly* what
>scale is used, just to it's "not the last one".

I use both methods. Sometimes the scales just happen to be ordered in 
a bank in a musically useful pattern and simply sweeping through them 
with a slow triangle wave works fine. Other times I pick out a few 
specific scales that are not "right next to each other" in the bank 
and have to send specific voltages to select those scales. It takes a 
few more modules to wire that up, but it's not difficult.

I suppose if you wanted to get really fancy you could offer a 
"program" mode where users could select which scales they want to 
stick into different voltage slots. Then they could sweep through 
that custom bank with a triangle LFO. Sort of like programming songs 
into your CD player.

I like your idea of being able to create custom scales and banks with 
a "scale librarian". That would probably eliminate the need for a 
"program" mode, but would require more work for the user (hooking up 
a computer to the module just to reorder a few scales would be a 
hassle).