Full damage outscales tanks
Unless you're a mage.
Not even 
late game, whom were meant to deal with high health / resistance targets wont do absolutely anything due to not having the oomph to even tickle certain champions.
There's another option to just kind've ignore the tanks and create opportunities to kill primary targets, this style sortve resides with 
... Good luck getting through the barrage of ADC slaves/slave items 
The new runes are a step in the right direction but not really fixing the problems with midlaners in general.
*Lack of item diversity and build paths. It's hard to accumulate really high AP that will keep up with ADC scaling. There should be items that deal with shield stacking and targetted ally abilities. Utility AP items doesn't have to mean another 
incident or things such as 
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Lack of magic penetration. I think there should be items built out of void staff/liandries that are extremely expensive but rewarding for cases of there being double/triple tanks in one game
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is weak and inefficient. There's no point of buying it unless you are 
