Montreal and Boston were in the save division and the Leafs were in the west as you very well know. I disagree that the Bruins are the top rival. Montreal and Toronto is nearly 100 years old.
I go to Montreal several times a year and the 2 best barometers are bartenders and scalpers and they agree Boston still brings a buzz that Toronto doesn't. That might change with Toronto coming out of a 50 year coma but we shall see.