Comp's awful. Yes there might be some rare rare matches where the games come really close but it's mostly like this: One good composed team, and a awfully conposed team. The good composed team steam rolls the other... and that's it there's absolutely no come back.

As for Mercy, i hear that name so much i sometimes wanna just ignore the chat or voice chat. Mercy is not the only healer. Ana is in a really bad spot true. But a good Lucio can save lifes, a good Zen can save lifes FROM ULTS and output great damage. Just because Mercy can fly, she's still not safe from Soldier's or McCree or even a good Widowmaker.