Oni Ryuu... Perhaps I am not understanding correctly. Other than simplicity and any desire to gain Culture for a Unit, do you basically want different graphics for the same Unit for the Civ it belongs to?
Why not use an upgrade path in the Biq?
This is like the Great Leader in EFZI2 upgrading to a Civ Specific Champion, each being different.
You can have a Rifleman for All Civs and have it upgrade to each Civ with different Graphics by using different Units.
Each Unit can also have different settings as you prefer.
The AI uses this very well... the Only drawback is that the Unit requires upgrading so the Cities need a Barracks to upgrade them.
If you ever wanted to change the graphics for any of the units, simply change the Name of the New Unit Folder the same as the previous Unit for the position. This way you do not have to change the Biq or text files.
As for Landmines... They do slow and damage the enemy but only until they are destroyed. If on Roads or Railroads, they can also slow the enemy by damaging the Road or Railroad after the Mine is destroyed.
You can set them up where you can Airdrop them to an area you want to keep Mined. You can also use Mine Laying Vehicles to place and retrieve the mines but that is slow to keep up the Mine Field.
Many of the game changes we want have required a "Work Around" due to the Game Engine Programming. There has been some success with New Biqs but Without the Code we basically have to keep thinking "Out of the Box" and use what is programed in a creative manner to try an achieve the differences we want.
Probably most of the Modders have asked the question "
Why" about many programed game factors... I have found the basic answer is "
Because"

Like it or not, that is what was programed to suite what the developers wanted for the Civ III/Conquests Games and I seriously doubt that the Code will ever be released
