If I had to choose between the two, I would choose 6, but I really think that is should be 5.
5 is how it was before 2004, and the NHL was about to leave for a year. Bettman suddenly decided to change that, and add in the extra.
I remember mostly how Toronto's schedule was like prior to this riculous change:
The Leafs played their divisonal teams -Boston, Buffalo, Montreal and Ottawa 5 times, for a total of 20 games.
They went on a Western Canadian Road Trip (Calgary, Edmonton, Vancouver) once, and had a Western Canadian Homestand once, and had an extra random game to boot, for a total of 9 against those three teams.
That's 29 games in total.
Then there were the Original 6 teams: They faced Detroit 3 times, Chicago 3 times, and the New York Rangers 4 times. That's 10 games, making the total 39.
They played the rest of the teams in the Atlantic Division (Philadelphia, New Jersey, Pittsburgh, New York Islanders) around 4 times each as well, for 16 games. That's 55 games, leaving 27 to split between 16 teams.
Add in 2 games from the Southeastern team rather than 3-4, and that's 65.
Leaving 17 games between the rest of the West. From the Pacific division, they played San Jose and Phoenix 2 times, and Dallas, LA, and Anaheim 1 time. That's 7 games to make it 72.
In the Northwest, it was Colorado 1 time (always in Toronto, until last year when they finally played in Colorado for the 1st time since 1996), and Minnesota was either 1 or 2 times (I forget where). When adding in the 2 games, that would be 74.
In the Central, it was Columbus 1 time, Nashville 2 times, and St. Louis 4. That's 7 in total, for 81.
I guess I'm missing a game somewhere (most likely Minnesota). I could be shakey on a few numbers, but I think I mostly got it right. This is all from memory you know.
Anyway, that's generally how the scheduling was for Toronto, and it was decent. Could it improve a bit? Sure, but what we're getting now isn't improvement.