With all that extra MR per level, I'm actually concerned about a particular item.

Sorcerers shoes (yes this isn't about Void staff).

Now I'm not the most knowledgeable player, but my understanding of early flat pen was that it was stronger against low resistance targets. Since some champions didn't gain MR per level, flat magic pen items were actually kind of useful. But the only item you really got for specifically the flat magic pen was sorcerers shoes (it's my understanding that you mainly get liandry for health a %health burn).

Now that people are going to get MR per level, sorcerers shoes may end up being a poor choice of footwear. This may lead to mage players grabbing a more defensive or utility based boot option over it.

What do you all think?