I tried your map, it is great. I did many games with AIs only, to test the balance of the countries, and I noticed some problems:
- England wins most of the games (as in the normal game)
- USA and Japan are particularly weak.
I did a slight adjustment, which seem to work quite well : I can still see England and Germany win the game, but also Spain, USA, France, Russia or even Austria ^^
Here are the changes :
England : Army offensive & defensive factor to 2. As a tradeoff, army cost is lowered to 5.
USA : Army cost down to 3.
Japan : Navy cost down to 4.