$8.5m is going to be the bottom range, unless he is willing to take a really significant discount. Ekman-Larsson signed for $8.25m a year ago, adjust for the increased cap and that is $8.6m+ this summer. Pietrangelo is unquestionably better than Ekman-Larsson.
Pietrangelo might not have the individual award, but Doughty still isn't a terrible comparison. He got $11m a year ago, which is the ~$11.5m Karlsson got when adjusted for the cap increase. Karlsson might be better, but his injury issues will have impacted the deal he got.
I'm still expecting that it will probably be a number beginning with 9, but his agent has an argument for more.
As for trading him, he has a full NTC and we'd be trading him from a position of pretty significant weakness.