I don't think he's been great or anything, but a fluke Cup win is a decent legacy and he took over a team that was led in scoring by David Backes. He had some nice kids in house that he semi inherited (he was in the org already before they promoted him), AP, Oshie, etc but most of the cup winning pieces were his adds (O'Reilly, Taranseko, Binnington, Schwartz, Schenn, Bozak, Dunn, Thomas, Parayko, etc).
Now, he would be leaving some caphell behind but most of it is moveable. A new GM would have the choice of retooling around Thomas/Kyrou/Buchnevich or just tearing it all down. Could get a bucket load for Thomas & Kyrou (both are on long term, decent money contracts), a few others moveable by themselves like Hayes, (Fuck...Hayes would be one of my favourite 3C targets if they made him available), Saad, probably Parayko as well and the shitty contracts they have are either moveable with retention (Schenn, Krug, Faulk, Leddy) with a decentish return, or dumpable imo with the cap finally starting to rise fairly quickly year over year. Binnington is maybe the only one they're stuck with but he's rebounded to not being terrible this year, so he might even be moveable in the off season.
Not so sure if he wouldn't have been a better play than the Glasses gang we've rolled with. Biggest trap he fell into was clinging to a group of veterans that won him a cup for too long.