no one could have predicted Cory's downfall and I agree it's was a solid contract at the time
overall the Devils don't really have any bad contracts, I guess some people think Zajac is overpaid but he's consistently been solid and fits the bill as a "Devil" type of player
Karlsson
Panarin
Stone
Duchene
Bob
Hayes would be a nice pickup like it was stated above
some very interesting names this summer, Devils can easily afford to offer and match a serious contract
The Devils will likely need to sign someone to get to the floor if Cory is bought out/on LTIR. The problem with the players you listed is they will have multiple suitors if they make it to FA and the term they will command. Shero addressed this.
""I've said all along, with the support of managing partners, Josh (Harris) and David (Blitzer), that you don't build a team that's rebuilding through free agent signings that would handcuff you in 3-to-4 years," Shero said. "Doing something for the sake of getting a little bit better, or to just say you're doing something, is patchwork and not a plan. There's only one way to do this. The idea is to build something that once you do build it, you're in a good position each year to have a chance to make the playoffs and at a certain point you're considered a Cup contender."
Five Questions with Ray Shero
I personally would have no interest in Karlsson, Duchene, or Bob. Panarin and Stone will be highly sought after. Signing high priced UFA's is no way to build a team long term. When these types of contracts go bad they can really hurt a team as those players become unmovable due to high salary.