The Great Northern War and Crimean War were in very different eras.
Reading Peter Wilson's Europe's Tragedy: A New History of the Thirty Years War this seems a far more suitable period to cover than the Crimean War. I think the latter was mainly a rather disastrous siege of Sevastopol?
The Thirty Years War is an highly interesting time period, but warfare and diplomacy was too different to be a mere DLC for a napoleonic game.