I like the current capture system, its better than having the map room in the middle of the field, where any moron could spawn in the hangar that faced the map room and fire rockets or guns and kill troops.
However, I would prefer the following changes:
Put VH on the opposite side of the town. Put a map room between the VH and the field.
Put 2 VH's in town, add 6 mannable acks to town. Town still has its map room.
To capture a field, you need to take the map room between the field and the VH.
Town can also be captured by taking the map room in town.
Towns are the SOLE determining factor in rebuild time of fields. If you take the field but not the town, no matter how much supplies you bring to the field, nothing will rebuild until you take the town.
Capturing the town will give the attackers a VH to launch GV's into the enemy field and will deny rebuild time to the field they're attacking.
Adding a few manned AT guns in the field and town would be nice too

The state in which the country's CITY is at is what determines the rebuild time of the towns. If any supplies are received, they should REDUCE the time down to a maximum of 25% of the time they would take to rebuild, none of this crap of getting supplies in and everything rebuilding instantly.