Using the most out of a sombra pick

So sometimes I play sombra and my team go 2-2-2 and I am like.. "Will sombra be a good pick in this composition" than I usually just swap my pick to something to a different flanker which does more dmg and more acceptable like genji.

My question is, is sombra a viable pick in 2-2-2 and can do the same dmg as a DPS flanker like tracer or genji? How do I maximize my dmg on her, should I often go for support or focus on the tanks?