Most players agree that it’s harder and slower for the Allies to conquer Japan than to conquer Germany, but it can still be fun for the Allies to try it, and it’s possible for the Allies to win that way.
There’s nothing wrong with including one or two battleships in your fleet, but after that you’re going to see sharply diminishing returns. To attack Japan, you mostly want carriers, fighters, transports, and infantry. The transports will let you bring infantry over to seize control of valuable territories, the fighters will protect the transports along the way, and the carriers will give the fighters a place to land.
Unless Japan is being reckless, you probably can’t afford to directly attack Tokyo in the opening or middlegame – instead, you want to attack China, Vietnam, Indonesia, etc. so that American income becomes much higher than the Japanese income.
Finally, there’s nothing wrong with having the British support you against Japan, but I wouldn’t have them send fighters; the fighters are a little bit slow to reach the front lines, and they can be awkwardly placed on American carriers. I would rather have the British either focus on pushing northeast from India over land, into Burma and Indochina and China, or have the British send bombers to do strategic bombing raids on Tokyo.
Good luck, and happy hunting!