Suggestions:
Spitfires should be more likely to attack fighters first, hurricanes should be more likely to attack bombers. This reflects how they were used during the battle. It should mean a combined force would have a purpose.
The enemy planes should be drawn from a pool. In such a way if you concentrate bombers later attacks will contain more fighters.
 "Elite Forces: Clones"){kind=icon}
 "Spitfire: 1940"){kind=icon}
 "Fly Or Die Beta Version"){kind=icon}
 "Airport Madness"){kind=icon}
 "Micro Olympics"){kind=icon}