Sub-Strats to change War Win Percentages.
HTC could add sub-strats to each country that modify the percentage of fields you need to capture in that country towards winning the war and flipping the map. Some number would have to be determined along with salting them in across the medium back field of each country. They can artistically look like rail yards, steel factories and such.
Their structure would be strategic targets with about the same kill ability and rebuild\resupply ability as a town. Their purpose, as your bombers, or jabo, or tanks destroy them. The percentage of fields needed to win the war from that country is reduced from 20%. Very heavy auto ack would be reasonable due to their direct impact on winning the war.
Just as a town can be destroyed, an M3 or C47 can bring the place back up. If you own the next GV base or airfield over, hurray for your side wining the war sooner. Or hurray for that evil M3 driver or sneaky C47 pilot who gave up an hour or more to drive or NOE across a sector to stick you in the eye by bringing up the strat.
So the percentage destroyed of a substrat or combination of substrats destroyed would combine to modify the percentage of country fields you need in your possession to win the war. And that sneaky M3 driver or C47 pilot would be able to change the odds back to his country's favor in one or two trips along with the rebuild time controlled by the City strat. A detailed page from the clipboard would be needed to clearly show all country's substrat, their percentage damage in real time, and what percentage of fields are needed at that moment a country to win the war.
Targeted Outcomes or Downsides.
Those who don't care can furball or GV spawn fight like always. Those who do, now have real short term war like targets to impact the outcome of the war including the ability to stick the winning country in the eye at the last moment by resupplying.
In the end, you get a new map to do it all over again faster if one country gets it together to smash all of the substrats with strategic bomber missions and quickly steam rolls the minimum number of bases in concert. And you keep an open sand box world for the players who simply want to drop in for an hour and shoot at things. If a furball, bomber intercept or GV battle is happening near a substrat, funsies for them. Or they hunt up the usual offering of game play and not worry about the strategic war win.
The biggest downside, you will need bodies and a certain amount of coordination of assets to leverage the reduced percentage of fields to win the war quickly. On the up side, just as a last minute M3 can raise the percentage of fields needed to win the war and cut your success short. A single bomber or even jabo can suddenly win the war with the small number of bases you already have. Strategic options so to say instead of needing a hoard. But a hoard can do it like old times since the maximum number of fields needed will still be 20%.