as you may know, there is a an AGI patch called AGI-MIDI. It is used to patch the old DOS AGI-interpreters "to make them play three voice music an sound effects via a MIDI synth." See as reference: http://www.sierrahelp.com/Utilities/SoundUtilities/AGI-MIDI.html
As I see there is already a patch (ID: 1913900) which implements the output of AGI OneVoiceMusic via MIDI as Grand Piano. I think it could be of more interest to enable full fledged music and effects with three diffent voices as "AGI-MIDI" does.
It would be fine if the feature could be configured via the GUI as soon as there is an AGI game detected in the slot and optional via command line parameter.
For all game files are loaded by ScummVM interpreter, it should be possible to patch and control the games completely in memory without changing the stored files on disk.
There are no special MIDI instruments preselected in the games for all three channels, so it is possible to configure appropriate defaults for GM and/or MT32 and have them changable via the GUI.
I hope my feature request is of some interest to you.
I am following your project since it's beginning.
Thank you for this wonderful interpreter suite.