I'm calling this now, prior to U18s. But, my choice for the Canadiens and what I think would be a great pick for this organization is Konsta Helenius.
Sticking with him as the surprise pick. He reminds me too much of Aho and to be honest, his production D, D-1, D-2 and D-3 are just a little behind Barkov but not by much. He's dynamic and similar concerns were applied to Aho, but he is a top center in the league. Kid is a young 2006 too. Still 17 years old, lots of room to grow.
Helenius has a higher floor than Catton, which I think Catton is a harder player to reach his potential than Helenius. You win with players like Helenius. He's not your typical soft Finnish player. The kid has game.
@Goldenhands Agreed?