He's getting +12.5M on the open market on max term (7yr).
Cap is rising, teams are going to go a bit nutty with this stuff. The guy's going to give you 90+ points if he plays 80 games, he's first unit PP and can play the PK.
Right shot RW, so more valuable than your Leftie LW.
I think any team with cap is going to give this guy a poke and see if he wants to play there. I imagine there's going to be at least 18-20 teams that come-a-knocking, Toronto might be in best position to give him the extra year.
I honestly expect if this Rantanen thing blows up in Carolina's face, that they'll load up the truck for him. 14M+. They have no contracts that have to renew anytime soon for high end players.