If you are looking to have good quality and still get high FPS, check out this tutorial! FiremanRabbit shares his settings! With over 5k hours I am sure you can find some setting changes even a seasoned player could use!
Useful Key Binds:
Zoom bind with FOV at 90: +graphics.fov 90;graphics.fov 70
Fast headlerp snapback and other graphical changes: effects.maxgibs -1;graphics.waves false;graphics.lodbias 5;physics.steps 60;headlerp_inertia false;gc.buffer 4096
Bind these keys to whatever you would like. I use F5 for the headlerp command and Mouse2 (wheel) for the zoom bind.