As axis you need to considder also the focus allies are giving Russia into the eqation. Allies should be able to calculate the total attack force long way into the future. You’ll basicly see how many units Germany can attack you with turn 6 already turn 2-3, and how many soviet units are in place to defend. Then you must calculate the needed amount of US,British and anzac support Russia needs to hold.
If Japan goes for STB on Russia youll need alot of fighters there, but that should not be a problem since Japan should be loosing in Pacific very fast. Carriers and fighters is a good US buy because they have the strongest defence and yet their able to defend (russia) and attack land (japan). Goes without saying that you buy carriers first and fighters later.
A good amount of trannies is also the way to go, as bringing the land units stationed in US (8 trannies needed with Brazil), Australia (3trannies) and Canada (1tranny, might be better of in the pacific in some games) into play is vital for winning the game.
US can sail tranny from z101 to z51 turn one, then take Brazil turn 2 or sail to New Zealand (good tactical place to be). I also use cruiser in pacific.
Example of US buys can be:
- 2carriers, sub, 2trannies (good hybrid, gets your land units into the sea early)
- 3carriers (maximum fleet strengt against japan)
- 2carriers, destroyer, 2subs (sink german subs atlantic)
- carrier, 3bombers (defend against sea-lion)
At least make taking Russia as expencive as possible. If germany have 60-70% its bad news for them.