At my level (mostly rank 4 legendary mechs) , Volti is only a menace in hangar showdown. And yet even there I am learning how to deal with it and in fact these last few days have had a greater than 50% success rate against it. 

I think in the current game nothing is so OP that it needs a nerf. The only exception might be compound beams. Not sure about tailsting since I haven't faced it much.