Unfortunately, I think his game is better suited to larger ice services and larger gaps between defenders.
I don't know how he's evolved in the last year, but before that there was a large divide in how he was playing and how he would have to play, to be an NHLer. He never had size or speed, and a lot of his tendencies were junior-styled.
Again, haven't seen him in the last year. Maybe he's quicker, or noticeably bigger, or has found a nice substitute for his low percentage play attempts. But it's a big hill.
He's "quick" in the shifty, agile way, but his speed and overall skating ability are still mediocre. He's a bit thicker than in the past, but still undersized, particularly given the lack of overall skating.
He has good IQ and can make some really nice, smart plays, but as you said there's a "junior" feel to him. Like he can be a borderline dominant player against his peers, but against men he does things that just don't work the same way. He has improved his 200-foot game, which is nice, but he's not a Selke-caliber player by any stretch.
Unfortunately, given his size, whether he makes it or not depends on if the offense materializes. The early returns aren't great. He's still quite young and obviously has time to figure it out. We'll see--I'm not particularly optimistic, but there have been bigger surprises before.
Just look at Reunanen--after his D+2 season he was looking dead in the water as a prospect; couldn't stick with a Liiga team, bouncing around between there, Mestis, and the junior league. Then out of nowhere he has an awesome D+3 season, and comes to camp in the fall and looks like he could step into the NHL (and now he's playing at a very high level in the AHL). Of course Reunanen didn't have an issue with his size or his skating, but the point is he was about the very same age as Henriksson when he took his big development jump.
Next year will be big for Henriksson. He'll have a season and a half of pro hockey under his belt and will be another year more developed. He doesn't need to come out and be a dominant force in the SHL, but he does need to start putting some points on the board.