As I get the sense you aimed to craft a roster and not just sort them by best-to-worst player at each position, I think there are a few changes I'd make.

1.) I think Rantanen with Hintz is a combination that'd I'd prefer to see. Each player brings a skillset more analogous to a common linemate of theirs (Rantanen has similarities to Robertson, Hintz to Mackinnon). For the 3rd member, I'd maintain that theme and put Lehkonen on that line.
2.) Aho is the picture of consistency and he & Teuvo seem like a safe place for Laine to land. It's a line designed to both maximise Laine's strengths and mitigate the risk of his limitations.
3.) Obviously I don't mean to say Barkov is the 3C, but I see his skillset being best utilised in carrying a line with a couple of lesser-known names.
4.) To that note, I see no world in which Maccelli doesn't crack the active lineup based on current performances and a line with he & Barkov could likely achieve a lot. I'd personally push for Tolvanen here for the fit (line needs a shooter & some physicality), but a case could be made for a few different players.

That would leave Lundell & Kotkaniemi anchoring a low-event shutdown line with another of the remaining players. Not sure I see any major issue with the D corps aside from wanting Joker a bit higher.

Thank you for your insightful opinion. Are you from Finland? I'm so excited about the four-nations and the upcoming Olympics. I changed it slightly now.