How about you increase ADC item costs??
You want to nerf mage's mana because they use abilities to wave clear...
So why don't you nerf ADC's autoattacks because they use them to wave clear? Statik Shiv? Infinity Edge?
Mages can't use autos to farm, that's why they had mana!!! Stop increasing mage item costs while leaving items like Zeal and Serrated Dirk cheap as hell.
Like I wish mages had 2 core items that costed 2600 items.