Right now best case scenario for both team and player to take this right to Dec 1st. Nylander could get a higher AAV, and the Leafs would get a lower cap hit in seasons 2 through 7. Just structure the contract so his salary this year is league minimum and the rest as signing bonus. Let's say the Leafs were offering 7 x $6.25 million to sign before puck drop on the season; they could offer him 7 x $6.55 on Dec 1st and still have a lower cap hit in years 2-7, but take a bigger hit this season. Nylander, if paid the league minimum (but with a substantial signing bonus), will only lose roughly $200k or so in salary.
I honestly believe that right now it's a loophole they will both exploit, to the benefit of team and player. Nylander will get at least $2 million more over the life of the contract by doing this, and the Leafs will actually get a bit less cap hit too.
I don't believe this was the original plan, but once they went by the first couple of games, it really doesn't make sense financially from either side to settle. And it's not like the Leafs are hurting right now.