Vesalainen reminds me a bit of Jake Virtanen. A player who has proven he can score at the junior level but, if he can't score at the pro level the way he has in juniors, plays a strong, gritty, physical two-way game. Because of that, I think both players have a very high floor but a lot of upside. Perhaps Vesalainen was simply rushed into the SHL like Virtanen was rushed into the NHL when they weren't quite ready, so they ended up playing a very simple game, just making sure to work hard without making mistakes.
I don't think I would pick Vesalainen in the top five, probably not top 10 either, but if I had to make a pick in the 11-15 range, it would probably be him. We don't know if he will start scoring at the pro level, especially in the NHL, but if he does, he could be dominant. And even if he doesn't, you probably still get a great third-line grinder with strong two-way play and a nose for the net.
(I know there have been some issues with Virtanen's work ethic as well, so it's not quite fair to compare the two. But I find their floor, upside and potential player types and development paths very similar.)