Based on your role and playstyle, here's a champion from a free rotation that may be worth trying out.
Go deeper with opponent insights!
Discover the strengths and weaknesses of your foes
Skill to Focus
Aggression is not limited to your matchup. Spreading your influence across multiple lanes through well timed ganks and roams is a big part about what starts the snowball. Diligent focus on this concept will be very important in improving your Aggression.