Here's my write-up of Sahlin-Wallenius from May. Great skates and two-way ability, but lacks ideal size and struggles with inconsistency and a propensity for his game to break apart a bit under duress. He certainly has the upside of a mid-pairing NHL LD with speed, but there are several IFs there, as well.
LD Leo Sahlin-Wallenius, Vaxjo JR, SWE JR
The inherent problem with analyzing chronically inconsistent players for the NHL draft is we naturally hope to believe that, with maturity and experience, they will iron out these inconsistencies and become the players they are capable of on a recurring level. The problem with this thinking is, while some players grow out of this by the time they hit the NHL, some do not, and it's quite difficult to properly identify the habits which lead to either end of this spectrum.
Leo Sahlin-Wallenius is one such player. When he is on his game, as he did mostly throughout a dominant season in Swedish juniors, the skill and potential are quite clear. He's a 6'0-185 offense-first defenseman who can fly in open ice. He's capable of passing and stick-handling which borders on the high-end, and he features an arsenal of shot angles and release points. This is a kid who likes to activate off the point and lead the rush and abet the offense whenever possible. He has the hands, feet and foresight to elude a player one-on-one from the point, and once he's in open ice he can beat you several ways -- nifty passing, deceptive shooting, or simply by beating a second defender with some fancy dangles and getting to an even higher-danger area himself.
Defensively, Sahlin-Wallenius is generally pretty decent. His gaps and positioning are quite good, he's solid against the rush and anticipates the game well -- this is a smart kid. Where he often fails is in his greasy-area defense, as this is not a player attuned to or in love with the physical side of the game.
But Sahlin-Wallenius' biggest problem right now is his propensity to disappear from games completely due to the adversity of getting hit or just simply playing against high-level competition. Without getting into specifics which will sound too negative, there have certainly been games where a couple of hits or mistakes led to more panic with the puck which led to more mistakes and panic with the puck for Sahlin-Wallenius. In a nutshell, he can unravel quickly and dramatically, and this is something which needs to be worked on far more than any physical aspect of his game.
If Sahlin-Wallenius can find a greater level of consistency, his tool-kit and smarts have the potential to lift him to an NHL second-pairing-type offensive defenseman who can also hold his own on all 200-feet of the rink. But he needs a few years of maturity and experience to get there, and that's the chance you're taking if you draft him in the 2nd round where he is normally ranked by the NHL draft consensus.