I have two small points of critique, but I'm really enjoying this mod so far. First, pathfinding (as has been reported by other people) definitely needs to be fixed, and it's not just for mexico. All siege scenes, showdown scenes, brawl scenes, etc. have buggy pathfinding and soldiers will just run into the walls blindly, in some cases getting stuck, clipping through walls, and making sieges or arena fights unwinnable. There's not a lot of main town scene diversity so it'd be nice of the soldiers had pathfinding to actually effectively assault a town.
Secondly, I think that if you reduced the accuracy of all cartridge guns significantly, ESPECIALLY revolvers, repeaters, and carbines, and reduced the accuracy of muskets and rifles just a little bit, the game would be FAR more realistic and fair without having to resort to an outrageously high friction number. I set my friction to .010 to help offset the damage falloff, but you could simply... make the guns less accurate, and then bring friction back to .002 to allow for realistic bullet physics, while also having a realistic feel to the shooting. Revolvers, repeaters, and cartridge guns in general in the time were NOT as accurate as represented here and in old west movies/games in general. You'd be lucky to get 5 bullets hitting the same target from 100 feet, let alone hitting the target with pinpoint accuracy. If I knew how, I'd just tweak the accuracy for all cartridge guns in my game to be reduced so that you always have a shooting cone, not a pinpoint shot. This would also make it so that musket infantry is actually still useful, instead of removing their effectiveness at range.