Howzit
I find reducing the dead zone is the best. I kept reducing it until i found 0 was the best option.
So in the end, I had deadzone vert and horizontal set to zero, crosshair sensitivity set to zero, and and turn speed at 80%. Take note though that aiming with the jetpack is waaaay sensitive. May want to turn down turn speed a bit when you hit that part. Or just get used to it (which I did eventually).
EDIT:
Take note I finished the entire game on Normal with these settings.