Forgive me for my complete ignorance on how the war is "won" but I thought that you only had to knock a country down to something along the lines of 5-6 bases? I could be completely wrong... But at any rate, if you don't have to capture them all, why not make 1 per country uncapturable in the first place.
Exactly put one indestructable, uncapturable base, surrounded by 5" guns, with no ordinance or troops, for each country on opposing sides of one sector. Place them in the middle, on the corner or any other part of the map. Surround them with other fields or leave them sectioned off by a large gap between them and the other cities. Take all attack potential from them and leave only planes, bullets, and gas.
This would have very little affect on the overall war. The only people it would affect are the people that like to ruin the fights by killing all the hangers or the CVs.
It would take the offensive threat away from these three fields so people didn't feel like they had to be flattened to win the war. The bases would be out of the win the war path.
It would stop the tension between the Bomber/Win The War types and the furballers.
It would give back the seminal part of the game that has been missing for a long while.
It would bring many vets back that loved the fights and quit due to the lack there of.
It would shut up all whines that stem from this.
and finally it would just add another reason to love the game even more.