Idea's for Kassadin's rework

So I'm a huge Kassadin fan, always have been, and I had some idea's of how his kit could be changed to maybe add some power but also remove some frustration from his kit.

Passive, Master of the Void: Kassadin's basic abilities gain bonus effects within the next 2 seconds if the target is a victim of Riftwalk, ( If the target is hit by Riftwalk and the ability is casted on them.)

Q, Void Orb: Damage increased to 100/140/180/230/260 + 0.7 AP. W, Nether Blade: Mana restore increased to 10/20/30/40/50% MAX mana. E, Void Rupture: Increases the radius to 400

Q: Void Orb: Kassadin fires a Void Orb in a straight line hitting up to 2 targets, dealing 90/130/170/220/250 + 0.5 AP, additionally Void Orb gains increased damage if used on a target affected by Riftwalk.

W: Nether Blade: No Cost, 10/9/8/7/6 Second Cooldown

Passive: Kassadin charges his Nether Blade passively dealing 10/15/20/25/30 + 0.09/0.12/0.15/0.18/0.22 AP magic damage on hit per auto attack.

Active: Kassadin draws upon the void to charge his next basic attack to deal 60/130/170/190/210 + 0.6 AP and restore mana equal to 5/10/15/20/25% of his missing mana. Additionally if the target is affected by Riftwalk, the value is changed to MAX mana.

E: Void Rupture: 70/80/90/100/110 Mana, 16/14/12/10/8 Second Cooldown, Cast Range: 550 units, Radius 250

Passive: Kassadin gains 5/8/10/14/17% Magic Resist

Active: Kassadin calls upon the void to blast a targeted area on the ground to deal 90/130/170/220/270 + 0.7 AP and silence all enemies caught in it for 1/1.2/1.4/1.6/1.8 seconds

R: Riftwalk: Mana: 50/75/100, 8/6/4 Second Cooldown, Range: 200 base range increasing by 100 for every 20 Void Essence, Radius 250

Passive: Kassadin stores up to 100 void essence, gaining 1 per every 225 units he travels ( This does not apply to distance covered when Riftwalking) and 5 for every spellcast

Active: Kassadin teleports to a nearby location to deal 100/200/300 + 0.5AP