Make mixer sound choices more user-friendly

The options for choosing virtual instruments in the MS 4 mixer are powerful but also pretty overwhelming, especially for non-technical users. Just trying to remember which VSTs and settings in that VST were used for an instrument in a prior score is hard and time-consuming. I propose an approach that turns the current design on its head by allowing users to define each virtual instrument once (e.g. whether its associated with a VST or soundfont, etc.) and apply it across scores, and in doing so, reduce the process of choosing which instruments to use in the mixer down to a simple list.

To this end, I have attached a basic UI design of how this might work.