I think the key to modding A&A is that, no matter the design, you need to stay true to why people play this particular game.
First, they want to move little plastic men and roll dice. If there are chits, they must not represent units.
Second, they want to engage in at least a partial historical simulation. There’s a reason the game is “Axis & Allies,” not “Guys & Tanks.”
Third, they want to play a game of minimum complexity.
I am of the opinion that, for somebody who plays A&A, the question of how long is less important than how exhausting.
Any map I participated in designing would be larger than the original. It would also include a number of magnified “cut-outs” around the borders for those territories that tend to be jam-packed with units.
I know a great mapmaker. Maybe we can dragoon him.
There is a cost to play each of the cards. Generals remain on the table as 1/1/1 units. Cards are drawn both at the start of the game and at the start of each round of turns. Some cards are drawn from a general deck by the player whose turn it is. Other cards are drawn by each player from a deck specific to their country. Some cards, called Events, are played automatically. Some cards have triggers – conditions that must be met.