Mandatory buffs to Garen
Every time he get a kill with his ultimate, he gains a stack of Justice. For every stack of Justice, his voice gets louder when he uses his abilities. And to actually make Garen seem like a threat, whoever is marked as the villain should have a debuff, with the tool tip menacingly reading "Justice is coming."
And instead of the usual "An enemy/ally has been slain" banner when Garen gets a kill, upon killing a villain, the banner should proclaim "JUSTICE!"
These must be implemented.