Originally Posted by
Sesto
Soldier is the go-to DPS this season. He's insanely powerful, and is never a bad choice.
Rein, Roadhog, D.Va, and Zarya are all acceptable tanks. Especially Rein. If you don't have a Rein on your team, you should.
Healers, Ana is the most preferred choice. She has the most broken toolset in the game. Lucio and Zen are acceptable too, though Lucio loses his usefulness in an uncoordinated team.
That said, play what you are good at. Do you have 100 hours on Mercy, but none on other healers? Don't be forced into Ana just because she's part of the meta. Either tell your team you suck at Ana (prompting someone to switch roles with you), or play Mercy. A bad Ana is infinitely worse than a good Mercy.
The same can be said for most characters. Don't play a hero you suck at, even if they're supposed to be good. Try your best to work with your team so everyone is playing heroes they are good at, while still creating a good team composition.