For more gameplay, there could be planes such as commercial planes, troop transports, bombers, or fighters.
-They could appear at airports and air bases, with a cooldown time of 30 seconds for fighters and 1 minute for bombers.
-Commercial planes would act like warships, while transport planes would function like naval invasions.
-Fighters would operate like military boats in the air, destroying troop transports as well as other fighters and bombers.
-Bombers could carry small atomic bombs or hydrogen bombs.
-They would take off instead of using a silo (if the player so wishes) and could remain unnoticed by SAMs.
-They would need to be countered with anti-aircraft stations or fighters.
-After using their atomic bomb, they would return to their original air base.
-Fighters would cost 1 million, and bombers 2.5 million.
This is just a suggestion you may take the basic idea and adjust details as needed.