So, seeing that the Style Dial is in progress, peaks my curiosity regarding another potential idea for a "one-knob" type solution:
 
FX Intensity knob.
 
Imagine you have several EQ or Compressor effects that are all working hard on a track or buss, and you want to either intensity them or back off on their intensity all at once. With one knob, you would essentially increase or decrease any non-zero setting of ALL plug-ins at once!
 
Think Waves One-knob.
 
Many times we work on tracks with multiple compressors or EQs and such and find the track seems to be lacking something. Not knowing what you can bypass all or individual effects to see if you've done damage or increase plug-in settings to do more, However, finding the right amount of everything might be a trial and error thing and turning lots of knobs in some cases. Without having to open individual plug-ins and reduce each effect's controls, you could just listen to them all reduced in intensity or power by using a single knob to pull back all settings, slowly to zero, or increasing them harder to see if that sounds better or worse. 

• If a plug-in control is set to default or zero setting in the plug-in, it is not affected when increasing or decreasing intensity.
• If a plug-in control is above a default or zero setting, increasing the intensity adds to the non-zero setting of each control, while decreasing the intensity subtracts from the non-zero setting of each control. 
• If a plug-in control is below a default or zero setting, increasing the intensity subtracts from the non-zero setting of each control, while decreasing the intensity adds to the non-zero setting of each control.
• Would/could intensify both FX Bin and PC plug-ins all at once, determined by DAW version or whether the FX Bin is enabled or not.

Just a thought. This could also be a useful way to put a magnifying glass, an "amplifier" on interactions between plug-ins on a single channel, so see how they affect each other at a greater intensity.