There is a misunderstanding here that I want to point out. Azir was gutted because his kit allowed him to do way too much too easily. Riot put him in a state that would finally take him out of the LCS spotlight(since he never really left it) to allow other picks to shine through for once. They are going to rework him so that he is no longer a massive issue but he is still rewarding to play.
Jayce may as well be just OP right now. There could be no issue with his kit, he could just have better numbers than most top laners. This is most likely true because he has been fine for years until now.