I like the Veigar changes except for...
E. Q is actually going to make him more fun to play IMO. W got a frequency buff (not that it actually matters since you can't land it on anyone that isn't cc'd or unconscious). R got a nerf, but I honestly don't care since I feel like Q's buff will compensate.
But E scares me. I play a lot of Veigar. Nowhere near as much as I play Azir, but Veigar is my third most played champion and I've been playing him since S2 when I started playing League. I like the little burst mage and I'm glad that Riot didn't want to change him into something he's not. But I'm seriously scared of the E change.
Why? Mid lane has a LOT of mobility. And before, his E afforded security when bursting. I agree it was too much. Don't mistake me; his E needed to be changed from an instant AoE stun that's better than some ults. But now, anyone that's conscious can just walk out without getting stunned, meaning that you have to rely on an inept opponent to get your burst off which is not fun for either party.
The idea of a ring stun is a cool one and I believe can remain, but it needs some security. It needs to be able to do something. And I have an idea that's piggybacked off what I saw elsewhere on the forums.
Turn his E into a skillshot like Anivia's Q. Anyone the projectile passes through or is within range of it when E is pressed a second time is interrupted. Upon the second press, the existing stun circle will be instantly deployed. This gives Veigar some security while also giving him the ability to burst down enemies if he lands a slow skillshot.