Neither of Garen's damage bonuses are in his hands

Thinking about this, This really bothers me.

Garen has 2 mechanics that let him "optimize" his damage; isolation damage on his E and the Villain mechanic. Both of these mechanics are completely up to circumstance and not in the hands of the player.

The Villain mechanic is obvious enough with how Garen has no say in how it works, so my post will mostly be about his isolation mechanic. Garen does not have the means to rapidly kill a wave or displace someone to make them isolated if they weren't already, and he can't rapidly gap close onto an isolated target unless he has Flash. He has almost no way of actually utilizing this unless he fights you somewhere you can't avoid it, like in the jungle. On the other hand, the person on the receiving end likely isn't even aware Garen has isolation damage to begin with (there is no special visual or noise to tell you he's doing more damage) and they're just suddenly going to take a whole 33% more damage off of pure circumstance. For how much damage his spin can do later in the game, that is enormous.

Why are neither of these mechanics, Isolation and Villainy, in Garen's hands to utilize? You could improve this champion greatly by giving him some mechanical condition that rewards him with E's bonus damage on a more consistent basis than what we have now.