Barring injury issues, on paper, I think the Leafs are measurably behind Boston, Washington, Pittsburgh, Philadelphia and Buffalo NHL rosters. If the Rangers sign their RFAs and shore up their D (there are still UFAs who can help them there), I'd probably put them there as well. They all have good forwards, good D (pending Rangers) and good goaltending.
I think Tampa is iffy with their UFA losses, older D and very aged Roloson.
I'm not sure what to think of the Devils - in the latter half they were great but at the start horrible. They're replacing the coach who was a catalyst for their improvement. Brodeur isn't getting any younger, etc.
I'm also on the fence with Montreal - in part because I just need more time to digest the changes they've experienced. Ditto for the Canes who one can never count out as being unable to sneak in - they won't be bad, Rutherford is too shrewd.
I'm not expecting lots from the Islanders (can Montoya carry on?), Ottawa (Anderson should help them be more competitive) or Winnipeg but I haven't looked at where they are with changes at very closely. I also don't know what to make of Florida who went through some massive overpayment on the UFA market though they probably don't have the goaltending.
From that, I'd guess the Leafs currently might have a crack at 6th or 7th in something close to the best case and maybe 12th or 13th in the worst case. If I had to bet on whether the Leafs would make the playoffs based on what I know right now, I would not bet that the Leafs would make the playoffs.