How to fix Lee Sin.
Remove all his invisible power.
Passive: INNATE: After using an ability, Lee Sin's next 2 basic attacks within 3 seconds gain 40% bonus attack speed~~, returning 20 energy on the first attack and 10 energy on the second.~~
Get rid of the energy restoration so he has costs and actually has to think about whether or not he wants to cast shit.
ACTIVE: Lee Sin fires a sonic blast in the target direction, dealing physical damage to the first enemy it hits and granting True Sight icon true sight of them for 3 seconds. If Sonic Wave hits, Lee Sin can cast Resonating Strike within the next 3 seconds.
ACTIVE: Lee Sin dashes to the enemy marked by Sonic Wave, dealing physical damage, capped against non-champions.
Fine. Still bs since it costs nothing and has no cooldown, but fine.
ACTIVE: Lee Sin dashes to the target ally or friendly ward. If the ally is a champion, both they and Lee Sin are shielded for 2 seconds and Safeguard's cooldown is reduced by 50%. Lee Sin can self-cast Safeguard to shield himself. If Safeguard is used, Lee Sin can cast Iron Will within 3 seconds.
ACTIVE: For 4 seconds, Lee Sin gains bonus life steal and bonus spell vamp.
Get rid of it. If he can't jungle properly without it, give his E some kind of Quinn-blind like effect on monsters.
ACTIVE: Lee Sin smashes the ground, dealing magic damage to nearby enemies and granting Sight icon sight of them for 4 seconds. If Tempest hits an enemy, Lee Sin can cast Cripple within the next 3 seconds.
ACTIVE: Lee Sin Slow icon slows all enemies in range and marked by Tempest for 4 seconds, decaying over the duration.
Fine.
ACTIVE: Lee Sin roundhouse kicks the target enemy champion, instantly rooting them for 0.25 seconds, dealing physical damage and Airborne icon knocking them back over 1 second. Enemies hit by the enemy-turned-projectile ~~receive bonus physical damage and ~~are Airborne icon knocked up for 1 second.
There is no fucking reason to root me. Riot has falsely stated it's so you don't flash the kick because it'll kick you the way he wants anyway, but this simply isn't true. Try it in a custom game, if you cleanse the root and flash it, it doesn't work like Rito says.
Also why on earth does it do more damage to the people that the original person kicked collides with?