Hint: Best strengths for admirals:
Enter the menu that allows you to assign your admirals to fleets, marines and bases. Their background color tells you what they are least likely to fail in :Blue is all fleets with any ships, red is any air force (carrier or airfield), orange is battleships and heavy cruisers, black is subs, and gray is marines. If you find a combination, for example orange faded into black, this means that you can combine the two.

Hint: Change rate of fire and accuracy:
You can speed up or slow down the rate of fire and accuracy of ships, marines and aircraft. Press R to slow down and increase the accuracy of the attacking unit. However when you slow down the speed of aircraft, it increases the rate at which they are shot down and it can throw off a torpedo or dive bomber. If you slow them down, speed them up, then slow them down again, they may not be accurate any more. Press L to speed them up and decrease the accuracy. However in the case of aircraft, it lowers the rate at which they are shot down. This tactic can be used to your advantage by using it on aircraft with experience of over 75. Because they are so experienced they will still make contact, but fewer will be shot down.