Um, thanks for that Harkonarson. The more I dig, the less I see a basis for distinguishing units on "soft" factors. Having distinct "sword", "spear" etc type units maybe ahistorical in a strict sense but does introduce an interesting element of "rock-scissors-paste" gameplay.

On the armour, I was also thinking the upgrades could be rationalised as part of the enhancement of armour - eg feudal sergeant may get 1-3 shields of armour, representing moves to light armour, mail and transitional. Maybe the knights would have to be stripped of some starting armour value to allow this to work.

I am not sure the weapon upgrades make so much sense (specifically being tied to iron deposits). At the moment, I'm thinking of disabling them. I actually think the period upgrades reflect the evolution of weapons fairly well (eg Chiv knights move to polearms; CMAA get a +1 to attack as they adapt to better armour, eg by getting pointed swords) although it could be tweaked.

On the unit sizes, what do you think should determine them? They are pretty important to the game, given the 16 unit limit. Raising all unit sizes to 100 would change the game dramatically (and arguably give too big a role to economics, with the likely cost of 100 knights). Presumably, the function of the different unit sizes is to try to induce balanced and realistic armies. But I just can't understand why spear units should be size 100 and other foot 60. I was thinking the spears are cheaper levy type, but this is conflating equipment with status again, and is probably untrue. At the moment, I'm thinking 40 for cav, 60 for almost all infantry, 100 for "horde" type units such as peasants or poorly trained levies.

Anyone have any reactions to the above? Is it worth pursuing a mod along these lines?