Champion Mastery Suggestion
sometime it's and sometime it isn't especially when you play Tank/Tanky DPS , because if you feed a couple kill you lose grades it's unfair playing that role.
if you play ADC/MAGE and you don't feed alright since you're ranged.
if you play TANK/TANKYDPS and you soak up the major portion of the damage IT SHOULD COUNT feeding in team fights should count less, in lane yes , team fight no , i think what matter in team fights is how much damage and peeled for you team as a tank/tanky dps.
ASSASSIN grade should be on how many kills you managed to do
SUPPORT on how many assist you made (and it's working well) even managed to get S+ as Bard so. I think it's the one i like the most actually.
JUNGLER: objective secured,kill,assist,gank.