Not op, The problem IS you're comparing him to other AD champions, He was never made to BE LIKE THEM.
Hes the first ranged carry whos a bit tanky, so while you whine about him being too strong, think about bruisers who are tank/meelee or mana bruisers (the ap equivilents, like ryze) Its only natural ranged ad gets one.
Then you cry because it isnt easy to kill him vs another ranged carry, DONT USE A RANGED CARRY TO COUNTER HIM THEN, CC him, rape him, he goes down. Keep out of range or have better sustain, and outfarm him.
He isnt op he just isnt item dependant and he isnt like any other champion yet.
In other words, I think his burst damage is a bit too much and his passive can get a little too many "stacks". So I do agree he is OP atm and with a little nerf he will be more suited for this game.