Two big ifs but if NJ did not just acquire Taylor Hall and Gaudreau has little interest in committing to Calgary long-term, this seems like a trade that could really work. Value is not too far off, but if both players are would be interested in playing close to home long-term, then I would imagine Shero/Treliving would sacrifice that for having the stability of a long-term star.
I wouldn't add anything from an NJ standpoint, even if I do agree that Gaudreau is likely worth more. It's a lot like the Hall-Larsson and similarly the Subban-Weber trade. If Calgary was truly trading Gaudreau -- which is unlikely anyways -- I think getting a caliber of player like Hall is better than taking quantity over quality.