You mean it makes the sim crash? What crashes exactly?
Assuming you’re talking about control sensitivity, before editing any config files, you could adjust sensitivity curves for your controller in the MSFS settings. You could create a profile with specific sensitivity curves for the C208B. Use that profile when you use the C208B.
The problem with editing config files is that if a sim update includes an update to the C208B, the files will get replaced and you’ll have to edit every time, unless you make a mod and put it in the community folder.
In the flight_model.cfg, I would start with:
elevator_scaling_table = 0:1
aileron_scaling_table = 0:1
rudder_scaling_table = 0:1
Change them to something like:
elevator_scaling_table = -0.1:1.0, 0:0.2, 0.1:1.0
aileron_scaling_table = -0.1:1.0, 0:0.2, 0.1:1.0
rudder_scaling_table = -0.1:1.0, 0:0.2, 0.1:1.0
If you’re still not happy, you could try changing some of the stability parameters under flight tuning, but keep in mind they will affect how the airplane flies vs. just the controls.
Keep doubts about your controller on the back burner. There’s no reason you cannot fly the C208B comfortably with a joystick.