Before you let that Tabis change slide....

The 10 armor reduction means absolutely nothing. That was never the issue with that item to begin with. All you did was mindlessly buff both its early and late game.

If you're so adamant about keeping that passive, why not make it scale with level? e.g. 7% aa dmg reduction -> 15% dmg reduction lvl 1-18. That way it's not some freelo 1100 gold buy to deal with ADCs at any point in the game.