I'll tell you what, I'll give you this. From a strictly habs point of view he could possibly be considered generational, in the sense that the habs haven't had this type of prospect/player with this much potential and talent in literally generations. He most certainly could be a "franchise player" but that's as far as it goes.
As good as he is or could be, he does not fit into the definition of that of a NHL generational player. That said he does have potential superstar written all over him.
Lots of good things to look forward to for habs fans.