In I/O insta-prone in CQC is gonna get you killed. Unless, your target is unaware of your presence and is a short distance off, you can probably prone. But, with those quick confrontations around a corner, never prone. You gotta stay on the move.

I have a habit when being shot at to jump, prone in the air, and spin to look for where the fire is coming from. I still don't know if it would be better to just gtfo of there on foot and find cover or do what I normally do

Also, bind your other weapons to your mouse buttons. If you got 3-4 other buttons set them for pistol, knife and shock paddles/whatever. I can revive like crazy with my shock paddles set on my mouse. It's an instant switch from that to assault rifle/pistol etc etc.

I don't know what else to say other then make sure you're on servers with a good ping, and that you ping well. You can try those latency things where you change the setting. I never tried that though.
Nature is a powerful force. Those who seek to subdue nature, never do so permanently.