Gustavus Adolphus invaded Poland with his navy via Prussia (the area of Kaliningrad on your map).
I like how Hamburg connects to St. Petersburg. But how about this: make Gotland Island a (neutral?) territory and make Saaremaa and Hiiumaa islands (Estonia) 1 territory.
Then connect Gotland to Hamburg, Saaremaa-Hiiumaa, Kaliningrad, Stockholm, and Pomerania? And connect Saaremaa-Hiiumaa to Gotland, Stockholm, St. Petersburg, Estonia, Latvia, Western Finland. And erase the connection between Estonia and Southern Finland. (More Malamute Europe, less Troll Europe.)
Other things I do if the map was mine (? = I'd think about it more):
- Brittany to Ireland is cool (connect the Celtic traditions!). Brittany to England is less historical than the Norman Invasion or D-Day -- which went to (1066) or came from (1945) SW England.
- Cut Thrace in half? It will rock Bulgaria's world as is.
- Belgium: a language divide might be nice.
- The ugliest and least strategic part of the map: the shapes of Russia's bonuses
- North Komi, South Komi? Then have the the Ural territories, the Komis, Perm, and Nenetsie be one bonus of 6 territories.
- Murmansk, Karelia, Archangelsk, Vologda = another bonus
- Kama bonus: minus Perm, plus Ivanovo and Ryazan
- other Russia bonus: Novgorod, Pskov, Tver
- Austria: no Vienna city bonus?
- France: Langue d'Oc (or South France) and Langue d'Oil (North France, better with this name to include Brittany)? France is the second ugliest part of the map (for how it looks and plays)
- Spain: East Spain (Aragon, Valencia, Catalunia, Balearic Islands), South Spain (minus Valencia)
- add Albania to East Balkans?