This organization will go down with the ship if Malkin has started to regress. He isn't being traded and will retire a Pen.
Kessel is a complementary piece that can be moved out anytime we deem fit. He's a very productive player, but as was mentioned ad nauseum, Guentzel or two D can replace Kessel on the PP. Our PP has been good for a decade. It will continue being good without Phil. HIs ES numbers can be replaced by signing one of the 2nd line caliber players in free agency.
His iron man streak is impressive and on a team where we struggle to stay healthy, that's a nice thing to have. But it's not a big enough reason to keep said player.
We're not Cup favorites as constructed. We likely won't be next year with or without Phil. I'd look to get a bit younger and try and prolong our window while still staying competitive in the interim.
If we had a Jake Debrusk type player flanking Malkin all year, 71 is likely out of his funk earlier and we're comfortably in the playoffs. I want 87 and 71 flanked by guys who help make them better players as they age. Guentzel, McCann, Rust is a good start.