Orianna has been ball slapping everyone to death for too long
But I don't think she needs damage nerfs, it's more of a counterplay issue.
Enemies need a way to deal with her ball moving around murdering everyone.
So I propose a new effect: If an enemy champion clicks the ball while it's on the ground, they catch it and throw it at her. If the ball hits Orianna or a teammate, they're stunned for 2 seconds and take 50 + 3xOrianna's level (+60% of Orianna's ap) magic damage.