If a sequel is made, here’s some ideas:
Same thing, but in space.
New, multiplying zombies.
A map where you actually physically take over the world, instead of separate maps
A reverse game where you fight zombies
Multiplayer
It would be fantastic if it didn't randomly delete all my gold and set it on "-9000", so I had to make it all back. It would be fantastic as well if my civilian population hadn't gotten randomly stuck on -87, which stayed the same no matter how much I deleted.
hardcore, if bigger armies always won, the game would be no fun and someone would win immediately. It would be nice if you showed the dice, though that would make turns much longer and the dice might be hard to render.
 "Hands of War 2 - Expanded Edition"){kind=icon}
 "City Siege 2"){kind=icon}
 "Doodle God 2"){kind=icon}
 "Civilizations Wars"){kind=icon}
 "Infectonator : World Dominator"){kind=icon}
 "Aztec God Game"){kind=icon}
 "Age of Kingdom"){kind=icon}
 "World Rebellion II"){kind=icon}
 "The Great War of Prefectures"){kind=icon}
 "Primary"){kind=icon}