Have the Swedish rebellion fail and have the Danish integrate their union more closely. At the same time, integrate more of the Hanseatic states into Scandinavia so as to create a bourgeois mercantile class.
With no Swedish rivals and, ITTL, a larger mercantile and military navy, they actually get into the colonial business. Although they do take Vinland for the fish/fur trade, a lot of money is also made on sugar.
Let's say that the Dutch never get free--they go to the Austrian Habsburgs and largely become a part of the Germanies. Have Scotland stay independent and have the London-driven Puritan revolution quashed by absolutism.
Also, have the Danes stay aloof from HRE affairs--an Austria that includes the Dutch may be able to use extra Antwerp money to crush independent Protestant states to a great extent. Or they collapse quickly, and Scandinavia stays trade focused.
Scandinavia, robbed of its two main competitors to a great extent, moves into northern Brazil and the Guyanas, taking advantage of Portuguese weakness to dominate Northern Brasil, the Guianas, and parts of the Caribbean (plus a small Asian empire)