I disagree that he needs to shoot more. It's kinda part of the road that got his head so confused. He needs to drive the net more and go try and make plays in dirtier areas. That will make defenders cover him. If he's on pp1 he should play the tap back position. Playing high on the boards it doesn't matter if he shoots or not.
I'm not a Marner fan by any means. I feel like his assist numbers look good and are higher than his line mates because he never scores. For instance Hyman /Matthews can make a great play, but if it goes to Marner and he shoots no one gets a point. Same nifty play that ends on Matthews stick and it's a goal. That's just my opinion. I don't find him particularly creative or dazzling. Kessel and Lupol were a much more creative and dynamic duo in their last year. I'm not saying they're better, but in the o zone they were sweet together.
Guys like Draisaitl and Kuznetsov to me make beauty passes.