I don't know what it is, but so many of these skinny Swedish teenagers bulk up a lot as they get older. Remember being at the draft in Vancouver in 2006 when the Canucks took Grabner. I was near to a absolute beanpole of a kid named Patrik Bergland. He was just so thin you couldn't image him playing pro hockey. However, by his mid 20's he was 6'3" and weighted well over 200 hundred pounds. Could say the same with Pettersson (whose starting get increasingly stronger) and many of the Swedish kids. No doubt, other groups so the same, but Swedish kids, in particular, get drafted as very light players but then mature into big men.
Might be the Canadian system doesn't allow for smaller, lighter players to given much of chance. The need to win now, especially in Junior hockey, means that you want the early maturing kid. In Sweden, with the bigger ice sheets and less emphasis on winning at the minor league, skilled, smaller players seemingly are allowed more chance to develop.
The hope would be that Lekkerimaki is on such a path. However, at his weight, I think it would be a mistake to bring him over too soon and put against men Abby or into the Junior hockey meat grinder. Let him stay in Europe and play in all the international tournaments.
Would also say, there have been some holier than thou comments concerning Lekkerimaki. People claiming that others said Lekkerimaki was a bust after his poor start to the season. I didn't see much of that anywhere. Instead, people were providing an honest assessment of Lekkerimaki's play at the time. He had very bad start. Also, people recognized the factors interfering with his progress - the mono, injuries and such. It is a little juvenile to come on here and say others "wrote off" Lekkerimaki, when all they were doing is commenting on how he was playing at that time. In fact, it is a little silly to say that we now know Lekkerimaki will be a NHL star based on this one playoff series. There will be ups and downs in his development and along the way people will comment on these changes. Such comments are rarely written in stone but only reflect his present progression.