Hi,

I'm not sure if your doing this already based on the quote, but if not, try this for a problem with the low end being more sensitive.

Install the arm on the servo in such a way that at wide open throttle the arm is close to perpendicular to the pushrod and at idle the arm swings back to almost parallel with the pushrod. This gives you much greater resolution at idle based on the fact that the standard servo's output isn't linear to begin with. It might need expo, it might not.

This is just one way to fix the problem mechanically instead of using a multi-point mix, but it is worth a try

Later,

Willem