Today you can board a train to Brussels at Stockholm Central, main station, and the journey takes about 14 hours. Through these proposals it will be possible to board a train at Helsinki main railway station and be in Brussels in about 16 hours. By speeding up the trains the journey from Helsinki to Brussels will become less than 16 hours. If you use the eastern route, the Rail Baltica, it is also possible to reach Brussels, but it is a longer route, but will it take 16 hours ?.
Traveling to Estonia today, you have two possibilities, the fast route by air or the slow, really slow, by ferry to Tallinn. Why cannot you travel by train, Stockholm Central - Jorvas - Tallinn main railway station ? To make this solution to work without stops the proposals suggest the use of standard gauge railway. The result is that the same train can start from Stockholm and arrive in Tallinn. To make it still more interesting, the train can start from Copenhagen and still arrive in Tallinn or Riga (the last part is the magic of Rail Baltica).
A new station is proposed for Norrtälje to make it possible to board a buss for Arlanda airport without first travel to Stockholm City.