You should try watching Dahlin
Svech is great, but he's not as skilled as Dahlin. The only chance he has at going #1 is if the team picking #1 is afraid of taking a Dman so high like we have seen on occasion in the past. But I dont think there will be anything to worry about when it comes to Dahlin. He's as close to a sure thing of a #1D as we've ever seen at the top of the draft IMO.
As Metal just said above, if Svechnikov played Center I think more of an argument could be made for him going #1 if he has a remarkable year. But as a Winger it wont happen. Tkachuk probably has the best chance of anyone at usurping Dahlin IMO, but he would obviously have to have a truly incredible year to even make that a possibility.