Over the final 17 games in 2018 Ryan had only six points and those all came within a couple weeks of each other. Throw those out and Ryan was on a 50 point pace. Ryan has battled through three different hand injuries the last year, and somehow has had seven different hand injuries the last four years. Ottawa was terrible last year, but Ryan Stimson's passing data shows Bobby Ryan to be a decent player. (2017 on the left, 2018 on the right).
Ryan is a 31 year old winger and was the #2 pick in the 2005 draft behind Sidney Crosby. In Ryan's last 124 games over two seasons he has 24 goals and 34 assists for 58 points. As a frame of reference that's about Mattias Janmark levels of production.
Trading for Erik Karlsson is a complicated process made even more complicated by the Ottawa Senators insisting that teams take winger Bobby Ryan as part of a deal. This has been a persistent theme since the trade deadline when the Vegas Golden Knights almost acquired the duo. As far as I've heard the Stars aren't taking Bobby Ryan back despite that likely being the easiest path to completing a deal, and they have good reasons not to want any part of Ryan.
Erik Karlsson even had a bit of a decline in his most of his metrics last season. The Senators were just really bad. Ryan performs similarly to Brett Ritchie, but he's a much better passer and worse defensively. This isn't a bad player. If you get 2017 Ryan you're in good shape.
The image to the right is from Micah Blake McCurdy's hockeyviz.com. The profile breaks down the role a player fits into and shows the impact a player has on the game. Ottawa gave Ryan second line ice time at even strength, and in primary points (primary assists and goals) he almost performed at the rate of a first liner at even strength. He didn't get many secondary assists because, again, Ottawa was really bad. Ryan doesn't do much of anything on the powerplay either which is a bit odd.
Ryan is due $7,500,000 in each of the remaining four years of his contract, which is why the Senators want to attach him to an Erik Karlsson deal. Ottawa paid a $2,000,000 signing bonus on Sunday, and he's due one every July 1st for the remainder of his deal. The price tag is hefty, particularly given what he brings production wise, but he isn't an awful player. The Stars could get some use out of him, and perhaps even revive him with better linemates with a chance of moving him next offseason.
Adding Ryan with Karlsson would push the Stars about $4,100,000 over the salary cap assuming Mattias Janmark signs, and closer to five million over with a 14th forward added to the roster. The Stars could then move Spezza to get back under the cap, but that opens up another hole at center. Martin Hanzal on long term injured reserve is an option if he isn't healthy enough to play, but even that barely would give the Stars enough room.
A more likely and reasonable option is asking Ottawa to retain some of the salary owed to Ryan. The Senators would be allowed to retain up to 50% of what is owed to Ryan, meaning the Stars theoretically could take Ryan on at $3,600,000 which is much more in line with his skills. The Stars would still likely need to move Spezza and find a second line center, but it seems like that is part of the plan anyway given how aggressively they pursued John Tavares and Paul Stastny.
From everything out there the Stars aren't taking Bobby Ryan back, but if that is the difference between getting Erik Karlsson or not then the Stars should seriously consider it if they can get Ottawa to retain any of the salary. Ryan at a lower salary is moveable. If he ends up sticking around he's a fine player to have in depth.
The Stars are right on the cusp of trading for Erik Karlsson. They can't let an opportunity like this slip away over Bobby Ryan.