Well I've been fiddling around quite a bit too with the ministick setting and for me what does it is:
Deadzone = 0
Saturation X = 100
Saturation Y = 50
Curvature = 30
No Slider / No invert / No User Curve
This way I can slew it very slowly when pressing gently on it and the more I press on the ministick, the faster it goes.
I even removed the cms script from my CH profile since the above settings work perfect for me.
Cheers,