For Sure: Jamie Benn
Maybe, especially with a Cup: Tyler Seguin
On the way but need more longevity: Robertson, Hintz, Heiskanen
Needs improvement, but not impossible: Oettinger
Too young to know yet but on the right track so far: Johnston, Stankoven
That's 8 players, which is a LOT. Benn is the only certainty. The rest will depend on how long they spend with the team and for a few, if they can improve their numbers to an even higher level. I'd guess that 20 years from now, at least 4 of these 8 will have numbers in the rafters.