The first of these was posted to the .com mod forum a few days ago by a guy named Dearmad. He simply removed lesser units from the list of recruitable units for each level of barracks and removed peasants from all but the first governor's house. It's been a big hit, providing many people with lots of chosen warband and other elite units to deal with instead of the warband/town militia. These lesser units are still part of AI armies, but in much lower numbers and mostly on the frontier where better units aren't available yet.
I saw some issues with this approach, mostly the lack of disposable pinning troops. So I spent the bulk of today putting together my own mod instead. I made recruitment of a unit one level below the best available dependent on the presence of a level one blacksmith, two levels down on a level two smith, etc. This way, in order to train lesser units, the AI has to upgrade both the trader (to unlock the smith) and the smith buildings (to unlock the units). Peasants can only be recruited if the farm is maxed out for that level town. This forces some pop growth to make up for the large unit size of peasants and provides some squalor to offset the efficiency of the peasant garrison tactic. Finally, I added a health bonus to barbarian governor's buildings to make them a bit more viable on large and huge unit sizes. This bonus drops from 2% to 1% to 0.5% extra pop growth as the town grows, so that the boost remains more constant over time.
Both Dearmad and I have posted our mods in his thread on TWCenter.net and I'm off to the official site now to do the same thing. Please give it a try if it appeals to you and send me some feedback, I can't begin to playtest it well enough myself.
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