Almost NEED to test a few different levels by watching the "raw input" vs the "scaled input". Raw input is what your joystick is spitting out, the scaled input is what the game is using.
Best advice is to play each axis until you are getting a smooth "scaled" input. It takes a bit of patience and testing to get there, but it's a great tool to clean up minor input issues.
Just keep in mind that it is not a magic solution to a bad joystick. There is a point of diminishing returns.
If nothing is "helping" after attempting to adjust all variables, it may be time to drop another $70CA for that Logitech Extreme 3DPro.... (mine just wore out to the point dead band, damping, & scaling were no longer viable options to "band-aid" the raw inputs.