Even with the perception of being OP with his 51.9% win rate
Darius is hardly a contender for OP when vi sits at 15+% pick rate and 54% win rate. Why nerf darius before vi? Also, the main reason for darius jumping is because tanks became so powerful with CoC and darius is the only real counter to otherwise broken tanks.
You're about to nerf CoC again, which is what created this entire mess anyways, maybe wait to see how CoC nerfs affect darius and tanks and even HARDCORE abusers like vi first?