[Champion Concept] Alzio, the Battle-Mage ADC

Here is one of my many champion concepts I have and I just want some feedback on what you guys think of it. Thanks for reading :)

Meet Alzio, he is hyper-intelligent and manipulates pure energy from the universe to destroy everything in his path. He is an incredibly resiliant and versatile Battle-Mage, with a completely unique style of attack. His main role is ADC but he could manage Mid and Top as well.

Passive - You can attack while moving and your basic attack is a constant beam of energy that deals 10-20 (based on level) + 5% AP magic damage every 0.25 seconds, you have 475 range but can stay on target until 500 range. You do not benefit from Attack Speed or AD as they are, instead for every 1% bonus attack speed or 1 bonus AD you gain 0.5 AP respectively. Your critical strikes deal only 50% increased damage. Lifesteal procs normally. On-hit effects are reduced to 25% effectiveness.

Q - Temporal Waltz - Distance towards enemies: 175 - Distance away from Enemies: 450 CD: 15/13/11/9/7

Blink a short distance towards your cursor, if you blink towards a champion who you are currently attacking, refund 50% of this abilities cooldown and cause Your beam of energy to surge for 4x/5x/6x/7x/8x current tick damage. If you blink directly away from enemy champions the blink distance will increase 150%.

W - Overpower - CD: 18/17/16/15/14 - Cooldown begins on cast.

For the next 6 seconds, your beam deals 100% increased damage and slows your target by 4%/4.5%/5%/5.5%/6% + 4%/4.5%/5%/5.5%/6% after each tick of damage maxing at 20%/22.5%/25%/27.5%/30% slow, this slow can persist for the duration as long as you are attacking them and for 1.5 seconds after not attacking.

E - Defensive Siphon - CD: 16/15/14/13/12 - Cooldown begins on cast

Gain a shield for 1.5/1.75/2/2.25/2.5 seconds that absorbs (50/80/110/140/170 + 70% AP) Damage, additionally, for 6 seconds after casting, 30% of all damage you deal is siphoned into the shield, the siphoned portion can persist for the entire duration. Active portion is depleted before siphoned portion.

R - Energy from the Stars - CD: 150/130/110 - Range: 5000 - Control Speed: 600 - Damage Radius: 125 - Vision Radius: 400 - Channel Duration: 5 (not affected by W)

Channel your energy beam from high above the rift to strike down after a 0.66 second delay, Granting true sight in a small area and dealing 10/15/20 + 10%/12.5%/15% AP damage every 0.25 seconds to all enemy units within the beam, (200/300/400 + 200%/250%/300% AP total damage) During the channel you are able to control the beam using this ability and move it around at a set speed. You are locked in place, Casting normal abilities, Moving or being Immobilized/Displaced instantly cancels the channel and puts it on cooldown.