Hi,
can we get a feature to the Instrument Track to make it as a folder for the MIDI Tracks , so we can collapse and expand.
Then you’re using an instrument track as an instrument rack! How you dare! 
I do it all the time and I think what you suggest is a great idea. In fact, they should improve instrument tracks in general (the disabling/midi routing problem, to say one), as I think it’s the way to go and they could replace instrument racks perfectly (as you can use them as instrument tracks).