If he's ready to move on the organization would be stupid not to accept a 1st + for him.
Zero reason for him to cut his career short by several seasons just to grind it out in Pittsburgh. It's one thing to say you want to stay with one franchise then to suddenly realize you're going to have to work 2-3x harder going forward, in your late 30s, just for your team to maybe compete down the stretch for an 8th seed - that's if one of the other teams falls off.
Or go somewhere as the number 2 guy and play meaningful games, with better linemates, padding your stats, and elongating your career no longer being the sole focus of the opposing team for all 82 games.
Colorado, Boston, Montreal - they all make sense. But so do many others. I'd just like to see him play meaningful hockey again.