Riot: Fix idea for the Lethality system

I know you guys over at Riot are currently testing shifting the ratio at which Lethality deals damage to be 60% up-front armor negation and 40% scaling with level (from the 40% direct negation/ 60% over levels that is live right now). While I feel this is a step in the correct direction, I feel another big change needs to be made.

What if we take the 40% that will scale up depending on the target's level, and instead scale it up in accordance to the target's armor level? This would mean that if someone built more armor, they would take more damage, and people who built less armor (ADCs, assassins, some supports, etc) would take less damage from the item.

This would make Lethality more effective vs tanks that build more armor and less effective against the squishies that you don't want it to be effective against, which was the original point of Lethality, right?

Let me know what you think.