Nerf for Zed that wont affect his Assassination power
Reduce his power to minions. There is no reason Zed should be able to farm from far away. In most assassins like Zed (Talon, Katarina, Akali) the main thing you have going for you is the early game and denying farm. But as right now Zed can very successfully farm from a safe distance. If you take this away he will have to make some decisions on when to go in for farm, when to play safe, and when to play aggressive.