Winston might be my favorite hero, oddly enough, even though I didn't play a minute of him in beta.
He directly counters all the tryhard widow mains, tracer mains, and genji mains, not to mention he easily deals with symmetra and torb turrets.
Oh, and those bad matchups? Just leap away. No prob.
There's nothing more satisfying and dick-hardening than hearing a widowmaker or genji scream in agony as they're being electrocuted.