You can adjust the sensitivity via the app advanced settings, you want the roll on and off for starting to turn made slower.
It is shown like a line graph and you want to make a slight S curve.
The problem is start messing with one aspect and it tends to compromise something else.
A lot of it is technique, I always find it much easier to initiate very slight yet consistent movement if I rest my hand on the controller and apply pressure the way I want to go without really holding the stick(s) at all.