Heel rest:

Heel rest, pedals

 

I feel like I am having the exact same issue that you described in your original post.

It takes a lot of pressure to get past the initial "sticking point" and then is kind of jerky throughout and requires more pressure than expected to adjust the gas and I wouldn't describe it as smooth.

Today I adjusted the throttle linkage cable since I thought it was maybe misaligned causing the cable to rub against the channel in the throttle body, but that did not help. I then started to think it may be the throttle body spring tension. Did you have any luck with adjusting the spring, and improving driveability?

 

If you have the same throttle body, what I did was take the throttle plate off and precisely centered it in the opening. Also since souch time has pass, I don't recall if I sanded slightly the edge to give it a miniscule amount of clearance. Since then I feel that it has improved. Also adjust the throttle cable tension to just before it starts to move the tensioner.