Additions in the future could include a large variation of maps, with different textures and generic feel. This could be created by making maps with tiles that cannot be accessed, this could bottleneck the combat creating more tactical opportunities for strategic players to counteract brute force.
You could turn the bunker into a map that only the player can see so as to influence a slight amount of base building, other players will not be able to attack this map. However players withing your alliance will be able to visit it.
On this map there can be:
A vehicle bay to see your ground vehicles.
A runway from a hanger which you click on to see your aircraft.
A barracks to see what ground infantry forces you have.
You could show off to your friends by having your most powerful squads lined up.
You could have a normal looking encampment where players within your alliance could sent gifts and you would receive them here, these gifts could include units or resources.
A training ground where you could pay a few resources to turn some regular scavengers into snipers or other infantry types.
Maps could have additional variation such as:
To the South you could have craters in the map or surface lava pools creating sections where land units cannot occupy but air units can. The change in height around the crater can be used to the players advantage as well. For these cratered maps I would create them around a weak spot or crater like this.
To the East you could take the battle to islands on the seafront, creating tight passageways for intense ground combat, yet providing a large area of aerial combat. For these island maps to the east I propose a design like this but with clear beaches or bridges joining the islands. I would create the same generic island but flat to the surface of the water.
To the North you could create and icy tundra where players will be warned about the devastation of thin ice, once again thinning down the area for ground units and providing a large area for air forces. However an area of surface lake where the ice has melted should be placed on top to restrict the area of the tiles. For these icy tundra maps to the north I propose using this style of place as the grid would simply fit in the middle.
To the West you could create a variation of monstrous mountain ranges where players could attack cliff sides to make them collapse, this could crush infantry and vehicles alike. The change hare could be that there could be advantage points in the mountain ranges for aerial vehicles to drop off artillery or snipers, this will increase the dynamics of the battles.
Another map could include sky islands that could consist of islands like this, there could be several of these joined by bridges of some description.
Additional maps could include making the map darker, basically creating this night time effect. In the maps you will have to use probes or other methods of scanning as in the darkness you will still be able to make out buildings and places to hide from across the maps yet you will not be able to make out units. Your units will have a radius of maybe a couple of tiles where the light from their vision will allow for enemies to be found.
In city maps there could be random patches of light from the few remaining street lamps or other sections of buildings perhaps, or in other maps such as the cratered maps or volcanic map the lava or magma could create light for a few tiles next to it such as if you were fighting around the edge of a volcano at night
Examples of these kinds of area are.
The placement of darkness on the maps could create new strategies to stick to the darkness then surprise attack your enemies.