It is harder now to hit 40% CDR without giving up significant Magic Penetration
As the title says, I'd like it if maybe the CDR mastery could be moved down a little or possibly separated from it's other effect of increasing the cap. Before, if you wanted to hit 40% CDR you could use scaling blues and get 15% from those, then 20% from items, and 5% from Masteries. Now if you want it, you'll lose out on 7% Magic Pen, or you'll have to use some combination of Ionian Boots and some other item, which again, loses out on the Penetration.