I think Dubas walked into a tough situation here. His mandate was to make the team competitive, and there was no reason to believe that after missing the playoffs by one point (after upteen consecutive years of qualifying) that he couldn't accomplish the task.
In his first offseason, his biggest mistake in hindsight was signing Jarry to a long-term, high dollar-value extension. With that said, the goalie market was thin, and locking up Jarry made some sense. He definitely could have signed him to a more reasonable length/term, however.
Another massive blunder that offseason was the Graves signing. It was another move that wasn't altogether awful on paper, but likewise, the length/term of the contract was simply unnecessary. Although these signings are in a different category than Dubas' signings in TO, there's nonetheless a similar pattern of shelling out too much term at too high a dollar value.
Finally, the Karlsson trade was another that is not as bad on paper as many (particularly non-Pens fans) believe. It was a masterclass in shipping out trash for treasure. I'm still gobsmacked that he was able to do it. However, not entirely dissimilar to the Tavares signing in TO, he made a move for the biggest prize on the market irrespective of the team's actual needs.
He made other moves with mixed results, none of which are particularly noteworthy. The Smith deal was good on paper, and kudos to Dubas for moving on from it quickly and seamlessly. There were some wins, too, most notably Eller.
On balance, I would characterize his first offseason here as a "failure," but not one borne of outright incompetence or ineptitude. He gave the coach a better roster than he had the previous year, and the coach got considerably worse results from it. For however bad Dubas' first offseason was, I place far more blame on the coaching staff.
In-season, I grade his Gunetzel trade better than most. He acquired some decent prospects and a good roster player. Inasmuch as we all would have loved a king's ransom for Jake (he was the best player available at the TDL), the reality is there were only so many dance partners available, Jake was closer to 30 than 25, and the return was decent.
This offseason, it's clear that Dubas - and presumably the org and ownership writ large - were more clear-eyed about the fact that the team is in need of a "rebuild," for lack of a better term. To that end, I believe all of his FA signings were prudent. He bolstered the team to the degree that he could without acquiring long-term anchor contracts. He took on some other teams' trash in exchange for picks, and frankly many of his acquisitions have bolstered our forward depth, something that has plagued this team for a long, long time.
The team is now in free fall, and I think Dubas' tenure here plays a pretty small part in that. The major flaws that sealed this team's fate were done over the course of years by JR and Hextall. And, far more importantly, this team's coaching has been an issue dating back at least 3-4 years, and arguably longer.
So, I'm no Dubas fanboy. Heck, I wouldn't even say he's been "good" here. But when I dissect the state of this team, Dubas is relatively low on my list of targets for ridicule. This team's demise was inevitable. It was accelerated by poor management before Dubas' arrival, and while Dubas has played a part in it, he certainly hasn't been the architect. His tenure here reminds me of a common occurrence in Silicon Valley where (oddly enough) female execs are tapped to steer a ship that's already sinking.