These ap item changes will make laning against zed even worse.
So zhonya's hourglass is getting cut 30 ap, which means that you will be less powerful if you rush that item that you are forced to rush. Not only that, it's cooldown is increasing, meaning that its cooldown is longer than zed's ult cooldown. Nice job rito games, it is so obvious you cater to ad assassins like zed.
) - Currently, the only reason to purchase Zhonya is because of the active effect. Due to these reasons, the loss of AP is not a big deal.