So lets say we move Kapanen for Kubalik. We then get a slower (yeah Kapanen is faster) version of Kapanen that is a little more one dimensional and is also inconsistent and trending down while older? How does that work for making the Pens better exactly? Sullivan won't even give a solid prospect in the AHL a shot that should get one, let alone a player that is worse than Kapanen defensively that is good on the power play. The age is negligible for sure, so forget that part.
Kubalik could rebound elsewhere, but I wouldn't move Kapanen for him.
Also, the 30 goal thing...Since his 30 goal season.
He's been on pace for 24 goals (in 82 games if it wasn't shortened) to 15 goals (on pace) this season. Meanwhile, Kapanen, who also suffers from inconsistency, has been up and down. He put up 44pts, then was on pace for 40+ again, and last season was on pace to top his 44pt season. This year he's been a bit of a mess, but that can be said offensively for everyone save for Sid, Geno, Rust, and Guentzel.
This isn't some diss to Kubalik, it's a "diss" to the trade idea. Kubalik might get moved for his RFA reasons and Kapanen for his consistency issues, but to move them for each other is like swapping a broken left leg for a broken right leg.
Chicago could move him to someone else and get a prospect in return that needs a change of scenery (maybe Chytil for him?). Kapanen, I don't know, I like him, so I want to see him snap out of it, but if Sullivan can destroy Kapanen, he'd make Kubalik quit the NHL.