You claim that the Swedes were 'always ... vastly outnumbered and having no help from other countries'. What is your evidence for this?
According to Fuller in 'The Decisive Battles of the Western World' at the battle of Breitenfeld in 1631 Gustavus Adolphus of Sweden was allied with the Saxony and that their combined army was around 47,000 strong compared to 40,000 in the Imperial army commanded by Tilly. He was therefore not 'vastly outnumbered' and had help from Saxony.
Tim