[Nonfractal]

I'd be interested in how these might be handled without adding knobs all over the controller. 
One of my pet hates with the slot.IT SCP is the rotary knobs that are hard to tune, easy to knock out of adjustment and impossible to adjust by touch only.

If what Nonfractal means by "impossible to adjust by touch only" is that there are no detents providing tactile sensation of distance travelled during a rotation movement, he is correct. 

Hmmm.  So, you dislike analog rotary knobs. What would you propose as an alternate?

Yes, no tactile feel of where the knob is in its rotation. 
Add to that: Full-left and full-right are both "full braking"with no way to feel how close to the centre you are ( or which side of the centre you are) which in turn means you cannot be sure of whether a right turn will increase or decrease the brakes or vice e versa.

Would linear sliders work? I see those on sound desks and wonder if they could be applied on a controller.