Nice response Kat,
Seems we might have some similar goals.
I went through investigating the knob setup some time back, you will find I made some posts about "Rotary Encoders", but this caused some mixed thoughts because, sure you can use the encoders when you are building and testing the patch, but when I am performing the patch, keep have to get up and down for any extra changes etc.. I have had this experience with many Multi effect systems over the years, so then I came up with an idea to solve this, (someone can take it and make money out of it), it is a Rotary Encoder that you can turn with one foot. A wheel to adjust the parameters with. But as I started to design it, I found it was going to slow me down greatly, so I decided to come up with a setup that I could incorporate the foot wheel later. This will be started after I finalize the module and the footswitch unit. Knobs you can control with your feet, how does that sound !.
'dynamic control' - hmmm very interesting.. I have been focusing on some patches that do this for the last week. Currently working on a trigger event every time a string is plucked, been trying to use the increase in the envelope follower to detect this. Mixed results.
'Expression Control' - Quite a broad area, do you mean like an expression pedal, or expressive parameter control influence by what you are playing at the time ? because it is the second that I am hopping will branch off of the work I am currently doing with the envelope follower in a more complex way, small steps.. !