Here you are likely to tangle with the high quality armies of Denmark or Sweden, so you cannot afford to be outnumbered. However the Danish army is likely to be split between Norway and Denmark proper, and the Swedish army is often involved with Russia. By this stage in the game Britain is one of the remaining great powers, both in Europe and the colonies. Secure defensively, Britain can deploy her full power into central Europe. She can probably freely chose between the competing alliances available.
Naval power allows marine raids to be mounted against vulnerable coastal targets.
Britain can now reap the rewards for years of patient building.