The general consensus seems to be that when you are attempting to protect your transports carriers fighters and destroyers give the best returns for the income invested.
However in a large scale naval battle requiring full movement the attacking player is at a disadvantage because their carriers cannot take hits without sacrificing the planes they carry. Meanwhile the defender can assign hits to their carriers the same way they would with battleships and have their planes land in adjacent friendly islands.
So, when you need something to turn the tables in the Pacific and break the defensive arms race what is the most cost effective purchase?
I would argue submarines but I’m interested to know what you think.
Submarine - This is the best purchase. Because you need to spare your carriers you need units that can absorb casualties. Submarines are the cheapest naval units you can field and they have the same combat score as destroyers. They force the other player to buy destroyers to defend their fleet and they lose economically paying 8 for a 2 when you only pay 6.
Strategic bombers are consistent in damage, but do they out damage 2 submarines?