To answer the "what specifically" question: one simple solution would be a PRV-specific thing: a drop-down list of all controllers to select which controller to show. That's part 1. And REMEMBER IT as long as the window is open, even if the contents of the window change by using 'pick tracks' or the like.
And then maybe slightly more complicated, eliminate the "by channel" nature of the controller pane and show those controllers that are WANTED for the ACTIVE TRACK only. Make it a preference thing, if some don't like this, but I don't see why that would be needed.
And last, while in the Controller pane, change the default for the smart tool so it doesn't grab onto a controller value whenever you try to draw anywhere near a previous controller value. #3 time waster today in my work