big concerns for overcharge rune
namely on bruisers and stacking CDR items to get lots of AD in addition to durability; I think assassins might be problematic too because they'll be double-dipping hard on CDR to squeeze out some more AD for their combos, but i'm a bruiser main so i care about bruisers
from what we know right now you get 14 AD for every 10% CDR you have that goes over the cap, and it also gives you 10% CDR by itself. so, CDR items that bruisers commonly pick up
(lol)
so, theoretically, a mana-based bruiser could run something like
and get an extra 56 AD and be fairly tanky. Swap Maw for Frozen Fist if you want and it becomes 70. And if the Udyr rework hits live similar to the last iteration, and he's still gaining CDR for his passive, you can add another 28 AD to that just for him.
Just a concern I have -- maybe I shouldn't be worried. ;)