Can i give some kayn rework idea ?

Hi i am lol player in taiwan server I come from Hong Kong I think kayn skill is interesting but kayn darkin better than shadow assassin so i hope send some rework idea to make kayn better than now

Sorry for my bad english but i hope you want to read it all

Kayn

PASSIVE: THE DARKIN SCYTHE

Kayn wields an ancient weapon and fights the darkin within it, Rhaast, for control. During each game, one will consume the other. Kayn hones his shadow skills by hunting ranged opponents, while Rhaast fuels his bloodlust by going toe-to-toe with melee enemies. If Kayn wins the struggle, he ascends to become the shadow assassin. If Rhaast is the victor, the darkin consumes his host and takes center stage.

Shadow Assassin: After being unseen for at least 3 second, Kayn next Basic Attack against an enemy champion will deal bonus physical damage

Darkin:Heal for a chunk of all spell damage dealt to champions(Cannot be re-cast on the same enemy for 5 seconds)

PS:Shadow Assassin need burst damage to kill , Darkin need change to no mana(Cost:current Health) and set to some limit

Q: REAPING SLASH

Kayn dashes forward, striking nearby enemies at the end of the dash. Both the dash and the strike itself deal physical damage. Reaping Slash deals bonus damage to monsters.

Kayn:Basic Damage need to nerf 20%-25% to champion and buff to deals bonus damage 20%-25% to monsters

Shadow Assassin: Deal more damage to champion

Darkin:This ability deals bonus percent-health damage against all enemies except minions.

PS:Kayn need to speed to kill monster but shadow wanna faster than kayn, This part Darkin don't need to change

W: BLADE'S REACH

Deal damage in a line that significantly slows all enemies hit.

Shadow Assassin:Leaves behind a living shadow that casts Blade’s Reach in Kayn's stead. The living shadow's Blade has increased range.

Darkin:Blade’s Reach get more significantly slows(99%,1sec) to enemies.

PS:Darkin not need a knocks up because it not fair to Shadow Assassin

E: SHADOW STEP

Kayn gains a burst of movement speed and the ability to walk through walls for a few moments. When he first enters a wall, he'll heal for a small amount and the duration of Shadow Step will be greatly extended. Kayn won't get the duration extension if he's in combat with enemy champions.

Shadow Assassin:Gain additional movement speed and immunity to slows when activating Shadow Step.

Darkin:Walk through wall will heal more health

PS:I think walk through heal better than no limit heal for a chunk of all spell damage dealt to champions because darkin make E worse than other one skill.

R:UMBRAL TRESPASS

Kayn may infest any nearby enemy champion who he has recently damaged. Trespassing into a champion makes Kayn untargetable for a few seconds. Reactivating the ability during this period ends the effect early. Kayn then wrenches himself free from his victim's body, dealing a burst of damage.

Shadow Assassin:Umbral Trespass can be cast from further away and resets the bonus magic damage from The Darkin Scythe after Kayn's exits his victim.

Darkin:Umbral Trespass deals extra damage as a percentage of the victim's maximum health, healing the Darkin in the process.

PS:Nothing to change because it is fair to other skill

I know I am not a skill designer but i think all champion fair better than always buff nerf to change