I fail to see how he can even improve now. Even his old issues with releasing the ball too late seem to have been ironed out.
He can improve further.
Last season some of us had criticized Neymar because even though he played well, he was slowing down our game and made unnecessary clownish tricks too often, which hadn't lead to anything except to pleasing the crowd or losing the ball.
Now, when he plays faster, with less unneeded tricks (it doesn't mean that he shouldn't do any tricks) he is even 30-50% better player than the last season.
People used to say: Neymar shouldn't stop doing those tricks and slowing down the game, it's who he is.
Well, it seems that he CAN stop doing those things and we can all see how much better he is now.
Also, he played his whole career "his game" with too many tricks, and he is playing only 2 Months in the current way, where he plays faster and when his overall game is way more lethal because of that (not to mention that the team also benefits more from his "new/tweaked" style of play). So, he is better both individually, plus our team is also stronger with "new him".
So, when he'll play longer in this "new way", he will be even better.
So:
1. imo, he can improve even more and we will see that in upcoming years (if his head will remain motivated)
2. also, there isn't a thing as "that's who I am, that's how I play".
= every player can improve and slightly alter/tweak his "who I am" in order to become much better player
Well done, Ney