We made a conscious decision to hide the MIDI fader by default because it can get very confusing to have the levels of a single destination controlled by two different means. Having a dedicated audio channel is superior in that you also have the chance to have inserts and EQ for each instrument. However, if you have a multi-timbral plugin that has multiple MIDI channels but only a single output then you won’t get the best from it. Fortunately most plugins like this do have the option to have separate audio outputs.