- Air bases only give their movement advantage in non-combat.
- CAP is not in effect.
- Bombers cannot attack ships.
- Submarines can only attack. They are considered 'non-present' when it is not their turn, therefore cannot block, cannot be attacked and cannot defend other units in their sea zone.
- Carrier born fighters have 'first-strike' capability vs ships when attacking (the same as the traditional submarine 'first strike").
These rules make subs strictly an offensive buy, as it should be. The fact that they can't block or help defend other units makes naval warfare much more vibrant and strike oriented (besides, something had to be done about all those sub vs sub battles that are more representative of the Cold War than WWII!).
The carrier rule I felt was needed because they need some sort of edge to make them as important as they should be, I felt they especially needed to be beefed up as offensive units. The 'first-strike' rule was the best idea I could come up with. I justify it by the fact that since aircraft carrier warfare was usually beyond visual range there was always that possibility of being jumped by carrier aircraft if you did not detect the enemy fleet in time. Land based aircraft would not have the same advantage since you would know fully well if you were within enemy fighter range and would therefore not be 'surprised'.