Here's something that needs fixing:
When the player or the AI does bombardment damage, and then the player reloads the map, like when opening the game, exiting a battle or exiting the designer, the damage done will be magically fixed to the maximum. This cannot be intentional, because it defeats the purpose of strike missions.
Also land combat needs fixing, because encircled provinces should not get new troops and troops should not be at full force if they are attacked from multiple fronts.