Remove Leblanc's Invisibility.
Make it so that when Leblanc is snared/stunned, the invisibility from her passive can't proc. She has insane mobility, juking and outplay potential as it already stands so pinning her down is already hard. But having her go invisible so that you can't execute her when you finally do catch her is just a little retarded and gives her way too much survivability and doesn't give her opponents enough reward for catching her. If LB get's caught, then you should be able to punish her severely, just like with other assassins, but at the moment that isn't the case - unless you have your team behind you to cover escape paths or an upgraded sweeper/pink on your hands.