I can see him getting 14.28 M x 7 (100m total) from someone.
He's too good of a player and will get whatever he wants.
He's in a tricky position though heading into free agency next season. Draisaitl will be 30 when starting his new contract, so he can't really go short-term like Matthews.
This will be his biggest contract and he will want it in one shot (7-8 years).
There are a few factors that will impact his decision to stay in Edmonton. Some of these factors are of course more generic such as whether or not he likes the city, teammates, team strategy, coaching, management, team's future, owner, amenities, and all those little things.
The next will be McDavid's future in Edmonton. Can he trust McDavid to stay after his contract ends?
This is where his love for Edmonton is going to show because he has to go first. He could be left in a tough situation holding a long contract if McDavid gets up and leaves at the end of his contract.
I think Edmonton will make him the biggest offer. They find it hard to attract superstars and he is a homegrown talent of the highest caliber. He will get a blank cheque from them without a doubt along with a huge signing bonus.
I can see them going 14 x 8 if necessary.
If money and familiarity are what he wants, he will sign with Edmonton right away. If he wants to go to a more glamorous city (NY, LA, Las Vegas, Florida) there will be multiple teams that go all-in for him.