A few silly ideas.......bear with me......
Is there a way that the instruments window could show different instances or places along its length without scrolling? I sometimes have the scrolling area off the page or in the dock. Something similar to setting cues maybe? That way you could have controllers (for a proteus) assigned down one end of the instruments window, click a button to see them, adjust them and then click it again to edit the standard instruments.
It would be like doing a metro version of a tascam 428 with its unlimited banks of faders. Maybe left and right arrows that move the instruments window the number of faders showing?
Then again it could be a new window altogether. A hardware controller window with not only faders and pans but switches and up and down arrows. A new plugin or app even.
scoot.