This isn't necessarily a bad thing for the Leafs. Niemela is currently setting the top Finnish men's league on fire as a 19-year-old gets to play another season as a 20-year-old and continue his development at home. This means it will be at least another year before he signs his 3-year ELC contract, giving the Leafs an extra year of seasoning before their young stud defenceman breaks into the NHL.
After his absolute howitzer of a one-timer in Finland's game against Austria at the World Juniors, we were all excited at the thought of the Leafs bringing him over to North America next season, but looking at the big picture, it's probably best he waits another year.