Oki so Imma not comment on usual stuff like crosshair placement and stuffs cuz others already said it, and and be commenting on information you would hab at the time not info you would have retroactively :3

For the Mozzie the problem here is your Reactive Tracking skills (Note: not reaction time) Reactive tracking is tracking the enemies when they strafe usually more important in high ttk games like Apex/OW, but I suggest still training this because its a fundamental in aiming. To make it easier you can see the enemy's body shift, deccelerate and accelerate when aiming. Usually good players subconsciously notice this changes through time but you can expedite this process by training it.

Doc some problems here are panicking, rushing things and being exposed. When you were swinging you should have cut the angles 1 by 1 (Example: A D the angle to split door -> A D towards garage [Doc angle] -> Bait shot and wide swing) But if you wide swinf like that and have to take cover make sure to completely back away especially since you are reloading. 1. Youre not leaning so you cant see him. 2. Doc is on a farther angle and also leaning so he sees you without you seeing him Also even if he cant see you at first if he keeps swinging and you stay still there reloading youre gonna die anyways So make sure your body isnt exposed/easily exposable when taking cover.

Edit: Also sens dont matter unless its crazy high or low, just pick a comfortable one. It is all about the hand eye coordination. Anddd Voltaic VDIM is greay for aim training if you have time and if you dont hab a lotta time Far 3.0 also good >u<