I'm sure I'll get "lulz homer" comments, but I'd rather be in TOR's position than BUF's.
Let's say the Leafs decide to below it all up this summer. Think of what they could get for Matthews alone. If they wanted to go in a new direction, I think they would be able to talk Marner into being moved and he could get a decent return. They'll save a ton of cap space when JT's contract expires. They would be able to get good assets for Rielly and Nylander as well.
In that case, they might need a little longer to make the playoffs than Buffalo, but I can see things clicking for them quickly like they did for the current core (which didn't take long to make the playoffs and has done it consistently). The new core might very well be better in the playoffs than the old core and BUf's core.
Personally, I wouldn't get that drastic. I think they should make a few roster changes and they should stand a better shot at competing in the near future than BUF. Not saying I expect them to actually win any time soon, but I expect even less from BUF.
I went with TOR over VAN because I think the East is less stacked in terms of really good contenders right now.
VAN has to beat out EDM, DAL, COL, VKG.
TOR has to deal with FLA, CAR and NYR.
Vegas and Colorado have actually won the Cup recently. With TB having declined, all the top EC contenders have yet to win it all with their current cores.