Each country would have its strengths and weaknesses.
Blue is obviously the largest, but connected to the most other countries; therefore, it is most likely to be under attack.
Red is large but can only attack blue over the land to start, neutering its early-game power.
Light green has the benefit and disadvantage of being disconnected from the rest of the nations, therefore allowing it to be both difficult to be attacked, and difficult for it to expand.
Green is massive but also frigid. It's basically Russia. Attacking it requires extra rations, but it also produces troops more slowly. The land is undesirable to conquer.
Brown is tiny but has access to the inner lake and a large ocean border. It is also bordered by green which is more likely to attack blue, and gold, which is also more likely to attack blue.
Gold is a desert, with all the benefits and drawbacks that entails.
Yellow only borders blue but is small. It does have off-shore islands which bring in profit from fishing.
Crimson holds only three tiny islands which are incredibly rich due to trade and due to an abundance of natural resources.
Grey is the most profitable nation per square mile of territory, controlling all trade in that ocean. It is a desirable target to conquer, but nearly impossible to siege. Blockading would be necessary.
White in the top right is nearly uninhabitable islands, not ruled by any nation. They are freezing but insanely rich in resources and iron.
Just an idea, of course.
My nation time. Beware, I shall be a master of profit!
Nation Name: Impor
Government Type: Republic
Backstory: Impor rests on the tiny little island of Senec, in the Sea of Impor. Its ships have regulated trade for thousands of years, usually through fair trade. However, it began as a pirate nation, which diplomatically elected leaders known as captains. These days, the leaders of Impor are known as Kapitans, in respect of this fact.
Location: Island of Senec (Grey on the map I colored).