Small Veigar buffs proposal

Since Veigar is in such a bad spot (because this is the truth and not just people who don't play him talking out of their ass) I have proposed some buffs for Veigar:

Passive: Equilibrium Veigar's mana regeneration is buffed by 1% for every point he has in AP. All spent mana is converted into "Dark Mana". If Veigar's health drops below 10%, he gets a rapidly decaying shield equal to the amount of Dark Mana he has.

Q: Baleful Strike Veigar fires a skillshot that travels globally in the direction it is shot in until it hits a unit. If it hits, it deals 300/350/400/450/500 + 60% AP Magic Damage in an AOE aound the unit. If it kills a unit, Veigar gets 3 AP.

W: Dark Matter Veigar summons dark matter to fall at a target location after a 0.005s second delay, dealing 400/500/600/700/800 + 120% of his AP in a 3000-radius AOE

E: Event Horizon The main reason Veigar was reworked was because his cage offered no counterplay due to its near-instantaneous cast time and enormous range; skilled Veigar players could stun their lane opponents from halfway across the lane almost instantly. The current cage has a 0.5s delay, and it has too much counterplay. I think everyone can meet me in the middle and agree with this quality of life buff:

Veigar summons a cage at the target location, after a 0.5s delay, anyone within the walls of the cage is stunned for 1.5/1.75/2/2.25/2.5 seconds.

R: Primordial Burst Veigar fires a target shot nuke, dealing 400/800/1000 + 120% of his AP + 80% of his target's AP in magic damage. If it kills its target, the cooldown is instantly refreshed.

Thoughts? I think this will put Veigar back in a pretty decent spot until he is truly reworked.