What does "level of player" have to do with it? I'm going to follow up shortly in another post.
He's never been a superstar, just a really consistently good player. I've seen someone ask before if we'd be having this conversation about Shane Doan if Thornton was traded to Phoenix instead of San Jose. Definitely can't rule it out.
Marleau is one of those guys who never had that extra spark of brilliance, for lack of a better term. Great wheels, good shot, good size, great pro. Seems like a coaches dream and he's had a hell of a career. But just not a defining player of his era.
So while I would say he shouldn't make the Hall, I'm almost certain he will because it's been proven time and time again that if you score 500 goals and you're a good guy, you'll get in.