Ok, seems our ideas about armies and war needs more working and consent in this spore's community.
Here is my proposal for the Army and the War Management System in Spore:
You must have a budget of how much number can have depending in your civilization happyness stat and your resources, you can bypass your max but your civilization will start to fall in all the other areas, becoming unhappy, and later your cities are much less productive in general and even your troops could start to desert over time.
Its real and simple, and I've inspired it in the ancient rome. This civilization did tremendous efforts to run epic campaigns around the old europe and conquer all. In the other hand Rome had high taxes, restricted freedom and people didnt rebel because they had a good development in the entertainment industry: gladiators, slave's market, and specially they did win almost all wars and used all the resources they can from their new colonies and converted cities.
To keep it simple,fun, still freedom and working:
Your city allow you to build, transform (into other type of unit in a city)or destroy any war unit. (You could also sell it to your friend species, but do you are sure you want them to have your army power?)
You have a limited budget you can bypass with consequences, the budget limit can be raised in many ways.
+1 for each city or colony, +4 for having your civilization extremely happy, +1 for every 10 slaves you have. This concept of budget can be expanded.
If you have a totally budget of 10 (not a very powerfull civilization) you could use those points as follow:
Vehicles: You need them to move war units without UFO. Vehicles can be controlled individually
Tank t 4 (War Vehicle) Power 30, Defense 30, Speed 15, Hitpoints 1000 Capacity to carry Units: 6
Airplane 4 (War Vehicle) Power 25, Defense 10, Speed 40 Hitpoints 800 Capacity to carry units: 6
Submarine 4 (War Vehicle) Power 30, Defense 30, Speed 20, Hitpoints 900 Capacity to carry units: 6
Ship Cost 2 (War Vehicle) Power 25, Defense 20, Speed 30 Hitpoints 1100 Capacity to carry units: 6
Helicopter 2 (War Vehicle) Power 10, Defense 10, Speed 30 hitpoints 400 Capacity to carry units: 6
WAR UNITS:s dont have max as you have enough resources to build them up but they need to be moved with a Vehicle, and when the vehicle starts to fight the war units go out and start fighting automatically. :They are moved in packs around their vehicle, if the vehicle is destroyed they are lost.
Robots and Mechs Cost (uses doble space in vehicles) (War Unit) power 6 each unit
Infantry (War Unit) power 3 each unit
Enslaved troops (War Unit) power 2-4 each unit (depending what type of slave are they)
small war vehicles or mounted creatures (War Units) power 4 each unit
The UFO is free from the budget as this is not considered a war unit or a regular vehicle. And you can only have one because its an extraordinary big machine with many uses out the war.
Your UFO can carry all the big vehicles you want around the galaxy.
You can build your army as you like: mostly airplanes and a few submarines filled with War Robots and enslaved infantry... or any combination you want.
I hope you see the vehicle are the most important but the harder to build and if you lost a vehicle you also lost their war units, a big damage dealer in the war and they cant be killed but are lost when the vehicle is destroyed (make them captured by the enemy?).
You will move small packs of vehicles to the war, and then automatically the crowd will look bigger when fighthing for the carried war units.
I like the simple idea of making small units unkillable until the big vehicles are destroyed, this does war more easy and watch your entire army fighting makes yourself feel very powerfull.
Enough easy with this system you only have to move vehicles and slect where you want to attack, the rest is automatic.
You would like to invest the time preparing your small units to fill the vehicles and make your army more effective, better than expend your efforts to build and control millions of units in every war encounter.
Even with this system I feel the budget limit need a max like 10 vehicles, just think 2 tanks filled of small troops would destroy any city in minutes.