Weight: heavy.
MIDI support is kind of secondary: www.youtube.com/watch?v=vnkJ0uYXMG8, e.g. how to export MIDI? discourse.ardour.org/t/export-an-entire-project-into-a-midi-file/88116
Ardour vmpk input: askubuntu.com/questions/709673/save-as-midi-when-playing-from-vmpk-qsynth/1298231#1298231