this may just be me but AI's pillaging my nation would be fairly new...
Yeah they do... but they take up what called a fairly large chunk of terrain... what i was proposing was amalgamating there function into farms and mines... and having them change in the way that cottages change
Clear Land---> Irragation--->Crop rotation? (whatever)
with the farms for instance giving a base +1 food and +1,+2,+3 gold for each level for instance
and the same for mines
and the same for lumber mills
it takes a while to generate the infrastructure needed to support large scale farming mining and land clearance. For farms to function there needs to be land to clear, good soil (civ is a bit silly in that respect.. a huge amount of land is not fertile enough to justify farming), mills, granaries, markets, wells etc infrastructure like that takes time to build up the same could be said of mines and lumber mills...
What im saying is that we treat villages and towns as part of the farm (which represents a large area... even assuming its only 20km^2 there could be easily a few villages, towns, cottages etc), mine or lumbermill
It would also help solve the money problem which is a big part of the game in the current version... and if that is fixed in the warlords patch it allows for a greater amount of money to be used for large armies..
Large armies are difficult to support as is, and they are fairly difficult to create not enough time... and to many wars to build up a big one but that might just be me.......
The system i envision is a slot based system (not sure if you can do it...) with the ability to build a lvl 1 improvement, lvl 2 improvement, lvl 3 improvement all the way to wherever..
With branches in the build possibilities... the ability for instance to go the full mining path
alluevial deposits--->open pit mine--->shaft mine etc
But with the chance of adding defensive upgrades to the path
--->defensive --->walled
outpost compound
With this you could for instance safeguard a rich deposit (i think hills,mountains etc should have a variable shield count when they are first mined.. some hills are richer some are poorer...) but it would take up land near the mine site limiting the ability to upgrade the mine it could if that proved to be to nasty take longer to upgrade the terrain with each sucsesive upgrade...
But you could also build better whatever you can come up with...
I have no idea if this is implimentable ingame.. maybe a modified cottage code?
even the idea of having fortresses taking up a square is a bit silly... i mean really how big can they be? a large fortress in the real world is a couple of square km...