Masteries
Would you like to have masteries dedicated for each champion? i don't mean ALL masteries but just 1 tier I don't know how the new runes/masteries system will but let's say it's like we have masteries now (with more impact). tier 1-5=normal mastersies,tier 6=keyston,tier 7=champion masteries
Champion masteries could be unique or shared with other champions having the same role (adc,supports,etc)
Unique mastery ferocity 1(Ashe) = Ashe first attack vs champions gets bonus from Forst Shots Unique mastery ferocity 2(Ashe) = Ashe can use ranger's focus without needing 4 stacks but the ability has 8s cooldown Unique mastery cunning 1 (Ashe) = Enchanted Crystal Arrow minumum stun duration from 1 to 2.25s Unique mastery cunning 2 (Ashe) = Frost shot bonus damage is applied also to enemies slowed/stunned by Ashe's allies Etc etc
i know it would be a really huge thing to do since we have already a lot of champions but this would help Riot to do what they want: more unique builds and different playstyles with the same champion
PS: i hope my english is good enough to let you understand what i mean