This game will always be unbalanced.
Since preseason I've noticed large amounts of complaints. Every season this usually happens but for some reason this one struck a nerve. I've been playing LoL since 2009. I've seen this game go through so many phases, and there has never been a point where the game was truly balanced. I'm not going to try justifying the current issues with the preseason(because this is what preseason is for) but rather to shed light on when this game was FAR worse. I'm going to use champions as a primary example, talking about previous items and talents would take me a lot of time to rant about. Here are some example's of when this game was much worse.
This guy used to only build sunfire capes.
Lux's ult could literally hit you inside the fountain, from the totally opposite side of the rift.
You could not kill this guy once he had a phantom dancer.
Innervating Locket made him a monster.
Sustain was out of control and his blood pool was about the size of dragon pit.
These are just a few out of a pretty vast pull of broken game play. I guess what i'm getting at is no matter how much complaining you do this game will always be the same. Just try making the best of the current state of it and have fun.