What to change first
Escape from Tarkov settings should help you see and hear. They will not replace ammo penetration, audio peeks, extract plans, stash discipline. Escape from Tarkov is a hardcore raid shooter where ammo, armor, and extract knowledge beat flashy guns.
If a habit only works in highlight videos, drop it after two failed sessions. Change one slider, then play a full session.
What to leave alone for a week
First: stability and readability. Fancy overlays and max settings that tank frame rate lose fights in tight interiors, long tree lines, high-traffic extracts.
Leave sensitivity alone for a week unless it is clearly broken. Hands need time.
How settings interact with bad habits
Bad habits wearing a new config still lose: ego peeking the same angle; running loud kits into night raids; skipping a backup extract.
If a change only helps in custom ranges, it is not a real change.
A simple config test
Test: play offline factory peeks, budget kit week, one-map extract quiz before and after one tweak. Keep a note. Revert if you cannot feel it in a real match.
Escape from Tarkov is not a settings simulator. It is a decision game with a mouse and a clock.
When you are done here, related resources can round out the same topic from another angle.