Ugh, you’d need to talk to Imperious Leader about that. He’s the one who put all that time and effort into making the Axis and Allies Revised Historical Edition!
As for me, I’m thinking of making a set of rules to balance the game board out overall, and add some flair that I just think is missing. Thinking the Axis should need a total of 15 Victory Cities combined to win, but that there need to be more VCs on the boards too. On top of added fleet complexity.
For instance, if submarines are the only units being attacked, then the destroyers should have to roll a hit to find them, then a hit to sink them, to simulate the fact submarines aren’t going to be just sitting there when a destroyer is present and waiting to be sunk! (but said submarines don’t get to return fire, they’re busy diving for the ocean bottom!) A la the movie Das Boot.
Also, given the size of the map…I dunno, I think destroyers might need a speed boost, at least in the Pacific (for both sides.) I generally say that you cannot change the map itself, since it’s a royal pain to “fix” it by changing where borders are, etc.
Likewise, the NOs have to change. NOs should be things you attain, not things you start with. In my mind. My opinion of course. But they are OBJECTIVES and the Objective of war isn’t to keep what you have, it’s to take what they have! SO like, Tokyo should be a 10 IPC objective for the US vs the US having a 10 IPC NO for not being invaded. Maybe Korea + Iwo Jima + Okinawa instead of Tokyo…just as an example. And it would have to be US Territory, not Russian. Russia would probably be a 3rd faction with loose ties to the Allies with it’s own victory conditions (Control of Poland, Hungary, Romania, Yugoslavia, Greece, Albania, Bulgaria and one of N. Italy or Germany maybe? And have no Russian territories controlled by Germany or Italy, would probably work fine.)
Battleships with plunging fire would probably be a big role, just because I truly feel that the battleship is the least utilized weapon on the board, as defined as the least purchased of all the naval units.