I think Juolevi's ceiling is a 40-50pt 2-way Dman. That would make him a #2 or in a really positive outcome (stellar D game) a #1 Dman for his team.
Vancouver does have some nice pieces in D but none of the really strike as a sure future #1. Tanev is told to be one, but I would wait the offence to light up first. Tryamkin, Stecher, Hutton make a pretty good future for them. I think Juolevi will the guy to have steady D and offence. So he could be their future #1, although not the best around the league. He has that 2-way game that could provide them stability and he could earn a letter some day who knows, he seems that type of a guy.
It's not easy to draw ceilings for players, especially for Dmen. When I watched Ristolainen in the FEL, he never struck me as an offensive guy, his highlights were pretty lame. So I thought okay, he's gonna be a defensive guy pretty much. As of now, Ristolainen has lit it up and his offence has been the better part of the game. Not that he's bad on defence but he has really grown into a good offensive guy and is becoming a good 2-way player, a poor mans Shea Weber some would say.
So it's funny how players develop and really anything can happen. Also it's easy to see how the 'Nucks fans and some others underrate Juolevi. The fans mostly due to picking him before Tkachuk or that he doesn't provide enough offence or whatever. But in Juolevi I see a very reliable Dman who's smarts are off the charts. That's something you shouldn't underrate. Tkachuk in your future TOP6 is nice, but Juolevi in your future first pairing is going to be even better, in my honest opinion.