Here's a detailed overview of the aiming settings in The Last of Us Part II (which also applies to Part I on controller). This should answer a lot of the questions I've been asked! Ultimately, the settings are a matter of personal preference, but there are a few things you should adjust to make hitting your shots easier and more consistent.
0:00 Intro
0:35 What is pre-aim?
1:25 Shooting in 30 fps
3:38 Acceleration
5:29 Ramp Power
8:54 Aim Assist
10:36 Sensitivity
12:35 Reticle Type
14:03 Other Settings
15:02 Outro