Literally all Garen needs to be viable is a Shield Breaker or knock back.

The buff doesn't have to be exotic like that Attack Speed idea they had on PBE a week ago. Just be creative. Give his Ult or his W an AOE Slow or a small knockback. Maybe even just a Shield breaker on his Q. Garen was designed to be a lane bully. Give him a creative way to stack conqueror....give him something to match this meta. It isn't hard to balance Garen and give him versatility on his builds riot. Come on!