i just had a brilliant!? idea

well everyone is complaining about % armor pen right? well what if EVERY SINGLE ARMOR PEN AND MR PEN ITEM gets its penetration removed but gets a flat amount of true damage? this flat amount can be balanced easier imo? so lets say you build sorcerer boots every spell gets X amount of true damage added.

this way armor is more useful but at the same time you can still deal with armor stacking.