Some ideas for modifications of stock maps:
Radar:
Radar parts have to be secured to a truck in the garage.
After securing the parts the truck has to be escorted through the main gate to the barbwire near allied first spawn.
Spawns change after the parts have been secured.
Allied spawn at Axis second spawn and Axis spawn at Allied second spawn.
After passing the main gate the spawns change again.
Allied spawn at Allied second spawn and Axis spawn at Allied first spawn.
Map time should be increased.
May be also two truck barriers.
Goldrush:
After securing the gold the truck has to be escorted along the tank route.
Not sure about spawn changes.