Good thought, but if I was the cocky kid GM of Toronto, I would ask for Pacioretty and a 2nd round draft pick for Marner.
You can't deal you top scorer AND a 2nd choice when you are rebuilding...
I would deal Paciorety for at least 2 or 3 upper choices.
Marner is another player like Drouin... Great playmakers. But they need someone to get the puck to. Actually, in MTL, if you trade Paciorety, there will be none left...