maybe add a special spot in the new maps like a spot that gives a double reinforcements or 50% damage boost when attacking from it.A mortar that would deal 2 damage to any block some what near it so u couldn't totally control the map. THEN maybe add 3rd party setups like blizzard all defense's are dropped by 30%. Then heat wave attacks are lowered by 10% you know were im going. Last but not least water drops as in the map will grow every 5 or 6 turns( this would be a game mode) the map would add to the edges maybe could tip the tides on a 50%50 game or save a game from 30%70. i dont know but these could really add more depth and strengthen what a work of art it already is.
ps: maybe add customization to your tile backgrounds that you control kinda way to show what you've done in the game or show off. thanks if you took all this in.