Lee sin, the blind monk is probably the best champion that riot games created. He was a very mobile, skill based assassin, who required quick reaction times, and good mechanical dexterity to be played to his best. unfortunately, he was eventually nerfed to the complete pos that he is now.
I'd write more, but I'm in the middle of class and I'm pretty sure someone could explain him better, because they have an actual keyboard in front of them.
Singed's design is bad and you should feel bad. If your hero's design is "walk around and cast one active ability and don't really auto attack" it's not good. He's stupid to run after, and he's stupid to run away from.
You'll see - Eternal love, that's what this is This feeling that I just cannot resist...OD