The Aurelion Sol nerf was unnecessary
Before nerfing his Q stun time, you could land 2 orbiting stars on the enemy early game when stunned. Now you could barely land 1 on time before they're unstunned; and that point, your damage doesn't scare them off enough to back off so instead they just initiate onto you even harder w/ no stun or any means of getting away from them.
During launch, he was perfect. There was obvious synergy made between the Q and E and by nerfing the stun time it's now made his playstyle extremely awkward, as nothing is adjusted to the way his stars rotate. If you were going to nerf the stun time, you should have at least increased the speed of the stars to compensate the damage loss. Let me not mention that he's the "newest champ" and is currently standing at a 2.6% pick rate. Anyway.
The excuse given to reason his nerf was terrible. It was something like, "A lot of players are having a difficult time with Aurelion Sol; therefore, we're nerfing him because he is potentially too strong in the right hands" 
Uh what? How do you suddenly jump from A - C without going over B. I'd really like some feedback from a red post to why this nerf was made. **As someone who managed to acquire 5th mastery on him during the first week, this nerf has made playing him too difficult. ** Initially, he was already extremely difficult to master and now he's just lacking.
_And the fact that you can't trigger your stun immediately is just stupid, but that's a different topic. _
he still is decent when combined with him.