Hi Lopsang!
I think your approach is pretty sound, and you wouldn’t be alone in puzzling out what to do with your Allies. From what you’ve posted I’d say the way you’re handling Russia and USA is fairly solid. The only thing that might be taking under advisement is how early you try to make an entry onto the water with UK. When I first started 1942.2 I struggled trying to make a carrier buy early on. It seemed the natural thing for UK to do at least coming from Revised and Classic. The UK1 carrier buy with the 3 infantry left over also seemed somehow to recommend this as well. I was also really intrigued by the sz37 hit as a possible way to open things up for the Allies. But over time, and many games botched, I found that this approach actually put a lot less pressure on the Axis than it seemed like it should. That’s when I started switching to UK Spitfires over UK ships, and really trying to get more power onto Russia/India. The thought being that UK was too weak and cash poor to get anything going before round 3 anyway (when USA could properly back them up) so might as well just by aircraft. Either Fighters or Bombers out of UK, and then dump the rest of the purse on India for 3 units a round minimum.
Buying Air on UK1 instead of ships was a big transition I felt, from previous games. And buying yet more Air on UK2 seemed somehow even crazier. But once I got used to it, it started to make a lot more sense. With no transports to protect in the early rounds, UK was free to launch the Royal airforce all over the place, and even to threaten the Japanese fleet after a couple rounds!
I’m a fan of using the US Pacific Naval forces in the Pacific rather than going full Atlantic right away. Often by the time the Pacific fleet backs through Panama to converge in sz 11, the US Atlantic force is already large enough that these extra ships from the Pac don’t make a whole lot of difference to the Altantic theater. I found if I kept them in the Pacific, or used their fighters to keep the Japanese on their toes, that this did more to disrupt the Axis than anything I could do with them vs G in the first round. For me the choice is usually between sending the whole Pacific fleet north, or sending the carrier group south around S. America and racing the battleship towards sz11. Either way though, I think your assessment about how to use USA is pretty dead on. They need a ton of Atlantic transports for the endgame to have any real impact on Germany. Usually this means 6 or more loaded transports picking up 12 or more units in E. Canada and dropping them either in Finland, France, or Northwestern, after the Brits clear a path (landing all US Air to secure the territory.) In my experience for it to work you need a double drop, 2 rounds in a row, which often means switching from France to NW Europe, so you can get another drop in with UK, while the US transports go back for more.
The D Day double drop seems to be the fastest way to persuade Germany to back off Russia and redirect everything home to the defense of Berlin, but it’s harder to set up here than it has been on some earlier boards. Its hard to really get anything going with USA until you have like 20+ ground units shucking around to threaten Europe, and that’s a lot of transports! So I think your initial instinct is correct, to expand USA transport capacity as soon as possible. That said, American bombers are a lot of fun, and make those ground forces a lot more effective when they start launching amphibious assaults with air cover. Just something to think on. The nation that invests in bombers early and consistently over time, often fairs well vs an opponent who neglects the bomber buy, even if you only use them in a normal combat role. Of course a killer bombing run, at the right time, can push Germany over the edge, taking them from an aggressive snapping turtle, to a shy turtle, who just hides in his shell and awaits the inevitable :-D
