Courage of the Colossus

Can we get Courage of the Colossus as a new keystone in the Resolve rune page? Aftershock is great for tanks and bruisers, giving them bonus magic resist and armor, however, Courage of the Colossus would be great alternative for the Aftershock. In situations such as when your health is low but you still need to engage the enemy team without dying. In that scenario, Aftershock will give you bonus armor and mr, but since your health is low the chances of your survival is low. As for Courage, no matter how low on health you are you get good amount of shield depending on your max hp, increasing your chances of survival. So I'm thinking Courage of the Colossus needs to be brought back.