Honestly? Good players learn to adjust to the challenges riot lays out before them. We all generally have a few champs we hate, and generally hate bad teammates. But.. we love the art, the champs, the culture, and we generally know that mechanical skill generally beats champ imbalance.
I mean.... you're discussing a game of 5th dimensional chess where there are currently some 131 different components, exponentially complicationed by Hundreds of thousands of different players.
Chess alone has 64 squares, 32 pieces, and produces 10,100,000+ possible ways for a game to unfold.
League is far more complicated, and balance is purely impossible. The best you can do with a game like Riot is to try to create outcomes where balance is the best of possibles, considering that every change you make to one champion affects them all, and their environment. That's why Riot continually has to add patch after patch, because one patch that solves 18 problems creates 320 new ones. But, the only way to reduce that would be to make all champs androgenous, have the same skills, and all items to be the same. That truly would be boring.