I'd love to see a mix of European and Pacific theater logistics to attack, it wouldn't change the outcome of the game we have now, but here are some ideas:
Submarine Bases: A huge target in the european theater, would take quite a bit of ords to take them down, and cannot be captured.
V1 Weapon Sites would be a nice target to add to the game (although the V1 would not be used in game as a weapon) it would make a nice ground attack target.
Factories: Holy hell there are at least 6 major ones I can think of, Airframe production, Ball bearings, Chemical, Refinery, steel, and Power Plants. Although a larger map would be required before adding these, logistically it would not hamper what a player could fly in game, rather if bombed could pose a penalty to the country who does not defend it. For example if we need 20% of each countries bases plus 90% of our own bases - we could throw in 60+% of industry must be undestroyed to win a war. Basically if your factories are bombed, you can't win the war.
Rain yards are a great idea, the trains like convoys would be used to supply bases - ship convoys would obviously deliver supplies to oversea bases, and even coastal bases. Rail yards would supply bases on land, however each "sector" of bases would require a railyard, which means it would have to be defended before you could knock out its resupplying methods.
The idea here is adding logistics to the game, which was a huge factor in World War 2, In aces high naturally logistics would be quite boring, however like above - if you don't defend it, you can pay a penalty.
Shooting in the dark with ideas, maybe some might be interesting enough to add one day
