Grim Views

First and foremost it's nice to have an open group. This way you dont have to ask for an invite to join and if someone in your group wants to invite someone they can.

Options > Social > Open group to: Friends
Options > Social > Group member can invite: On

Everyone has a different button configuration but one thing about FPS and voice chat is that having your PTT key bound to a mouse button (usually the thumb) allows you the full range of motion on your left hand while chatting:

Options > Controls > Communication > Push to talk: Mouse4

Before I go into hero specific settings it's also worth mentioning that your video settings at max are pretty but can also make it difficult to see sometimes. My recommendation is to keep textures and anti aliasing maxed out with the majority of other options downgraded:

Options > Video > Advanced
Local fog detail: low
Shadow detail: Off
*Effects detail: low (this is a big one, too many shiny effects to see well)
Lighting quality: low
Antialias quality: As high as you can
Model quality: As high as you can

Some character based key bindings can make you much more effective with specific heroes. I'll only list the major ones that have had noticeable impact

Lucio: Shift to crossfade - You hold down shift when you want to crossfade to sprint. This allows you to treat the shift key as a sprint key. Often times backing out of an ult quickly is the best way to help the group

Options > Controls > Lucio > Hero > Hold to crossfade: on

Mercy: I think the beam toggle comes down to preference. The 'guardian angel prefers beam target' setting has really changed my mobility though. You use shift to fly to players (guardian angel). If this is set to on then it makes it very difficult to select players not getting hit by your beam.

Options > Controls > Mercy > Hero > Toggle beam connection: on
Options > Controls > Mercy > Hero > Guardian angel prefers beam target: off

Soldier 76: Toggle allied health bars to on. I wish every class could do this. It's so you know if your heal will help others but the bottom line is that it improves awareness

Options > Controls > Soldier76 > Hero > Allied health bars: on

Zarya: Same thing as soldier 76 but even more important for Zarya

Options > Controls > Zarya > Hero > Allied health bars: on

Junkrat: Riptire can climb walls and it's especially effective on specific choke points where it's common to get it shot down. You can make the riptire automatically climb walls.

Options > Controls > Junkrat > Hero > Rip-tire automatically climbs walls: on

Toggle netgraph should also be something you're familiar with. I'm lucky not to have any performance issues but I do get laggy every now and then. It helps to pull up your netgraph for a bit. The orange blocks are the real danger and you only see them when there's game affecting lag.

Options > controls > miscellaneous > Toggle netgraph

and similarly if you do have performance issues make sure to setup your bindings for fps counter

Good stuff. I would recommend binding Melee strike to something like mousewheel up or down (only one of them), V is a terrible spot. Also, for Lucio, binding jump to mousewheel (up or down depending on what you want) is great for wall walking with his ability. Still keep jump as space too though. And on Winston, I have his jump attack and melee bound to mousewheel up and down respectively, so when I go ultimate, I can just spin my mouse back and forth attacking everything.

There is an option to limit your FPS too. Make sure it is not set to 30 fps

There is an option to limit your FPS too. Make sure it is not set to 30 fps

Good point! If your PC can handle it make sure to completely unlock the FPS and let it soar. This will greatly reduce mouse input lag because your PC will be able to process input at a higher rate and will be less likely to miss a handoff of the mouse input upstream.