Does Zed reeally need 25% Bonus AD ?

It means his AD ratios are artificially lower for most of the game.

If anything, his base AD should get looked at. He gets an execute passive on his basic attack but doesn't get penalized with a lower base values. Unlike pretty much every other champion in the game.

no, but its what gives him the edge in a 1v1 situation to give him the identity of a drop target assassin.

No, it's just there to let him kill towers faster.

A better passive would increase the damages of his other skills, rather than his autoattacks.

Annie get's a free stun so it seems fair. Can't an annie ult