AHII is full of great targets, Airfields, towns, factories, they get re-supplied automatically, there are roads, bridges, truck convoys and trains. But what if, What if the truck convoys or trains had to cross a meaning full bridges and that bridge could be a
target.
The bridge could be destroyed, and to rebuild the bridge or to rebuild a town, the owning element had to put an engineering set of troops in to rebuild the town, or bridge or airfield.
A base would have different types of troops, not just the assault troops used to capture a town, but engineering troop that could re-build the town or airfield, re-build a bridge.
The bridges or roads, railroads, would become strat targets, they would have to be defended or your airfield would not be automatically re-supplied.