For a player putting up around 40 points, I expect that player be contributing in more ways than the score sheet. Sven hasn't been able to score at a high enough level to make up for his warts. Maybe in the future he will be (heck, maybe even this season), but I see him as a player with a lot of flaws that just isn't offensive enough to overlook them.
Even Gaudreau putting up pretty nice numbers does a better job on the defensive side of the puck, and competes pretty hard. If he doesn't develop, he will not have a place in the NHL, as I expect the Canucks to start accumulating more talent that will eventually squeeze him out. Many players of his ilk end up in the KHL eventually, and I really do think that is where he will end up. Will be curious to see how he develops though - I wouldn't shoehorn him into particular floor or ceiling, but I am glad the Flames don't have him as a headache any longer, and particularly enjoy not seeing endless pages of arguments back and forth regarding him on these forums