If this team gets swept, I'm fairly certain no one outside Crosby, Malkin or Letang are safe.
I'd break it down like this. Crosby, Malkin, Letang are untouchable barring an absolute steal offer. Guentzel, Dumoulin and Murray wouldn't make sense to move. Guentzel is our best winger on a fair contract, Dumoulin is arguably our best all-around defenseman, and despite all the flack Murray gets, he's been the reason these games have been so close. Bjugstad, McCann, Rust, Blueger, Schultz and Pettersson aren't the issues. I doubt any of those guys get moved. They've all been good and having them here makes a difference.
People forget this team has standards and while some questionable moves have been made since 2017, they're still a good team and equally good moves have been made to make up for the bad ones. My only concern is the Penguins trading Kessel, Maatta or Hornqvist and getting some cap relief only to blow on it someone who doesn't fit in free agency. The only free agent I'd currently want is Eberle, and he's probably the only tangible option on the wing.
Right now you shop Kessel or Hornqvist. You either keep one or the other. Kessel has probably been our best forward so far and despite his baggage is still productive. Hornqvist is one of my favorite players and is a heart and soul guy but is a powerplay specialist making $5.3M a season. I think you move which one gives you the better return, which could be either depending on the receiving team. Logically you would keep Maatta and move Johnson, but I'm not sure if the Penguins are going to do that. Maatta is by no means someone I'd want to keep but if I'm deciding between the two, he's definitely the better defenseman.
I think our biggest issue is how we've thrown away our 1st round picks. I understand this is a win-now team and has been for the past 7 or 8 years, but look at our past 5 years of 1st round picks. Penguins draft Kapanen. Our 2015 1st round pick is traded for Perron. Kapanen and our 1st round pick in 2016 goes to Toronto for Kessel. Perron goes to Anaheim for Hagelin. Now, I'd say that's an instance where it worked. Sure, hindsight's 20/20, Perron was an established winger it just didn't work out. Hagelin was absolutely worth a 1st in 2016, he was arguably one of our best wingers that season, he fell off a bit but still worth it in my opinion. The Kessel trade was absolutely worth it. That said, 2017 we basically trade our 1st round pick and Sundqvist for Reaves and a high 2nd round pick. Our 1st for 2018, a top goalie prospect and Cole goes to Ottawa for Brassard. Once again, hindsight's 20/20 and we managed to salvage that deal for McCann and Bjugstad. I think if you're the Penguins you try to get younger, faster and more skilled. Slower and tougher hasn't helped us the past 2 years.