Fair point! I guess I'm thinking primarily about units with secondary weapons and/or equipment and reasoning about how Desirability could be used to impact equipment changes. I guess the prime example are Skirmisher units, which were using a ranged weapon as their primary weapon, but they were often also carrying a secondary melee weapon/armour. Like the (Javelinmen) "Peltasts" mentioned in the disucssion. The type of melee weapon isn't necessarily prioritised, meaning that they don't need to acquire the best swords or armour. Skirmishers can instead generally(?) have equal desirability for all melee weapons (or otherwise prefer lighter/cheaper ones) compared to the melee infantry line, where the primary weapon is more important. Another example would be units of melee infantry that used a mix of swords, maces, axes and so on, where each of those weapons had their uses, and at least didn't necessarily exclude the others. I know this clashes with the standard Weapon-based Unit types, but could potentially be used later on. Then there is the use of Bow/Javelin for Chariots and Mounted skirmishers, and Slings for foot Skirmishers, which might come down to personal preferences/training/economy rather than distinct and solid combat advantages. There are the Pike-and-shot units which would mix muskets and crossbows. Until muskets improved and crossbow use faded because of the extra training needed. A modern combat example, where I could envision Desirability to be used, is to increase the Desirability of AT weapons for the Melee/Skirmisher line, when they start encountering tanks. But if you're still encountering mostly soft targets, then that could maintain or increase desirability for Anti-personnel weapons. Desirability for better armour or armoured vehicles could be increased when you take a lot of damage, etc. So I was thinking that modifiable Desirability could in a sense be the result of your playstyle and circumstances. If you're building a lot of Artillators and Archers, then the Civ would likely specialise in archery. Maybe that would give extra promotions to Archer units and extra Science for improved bow technology. But the focus on archery could also increase the desire of your soldiers to use bows, even when they might be better off using other weapons. Just a thought. You could have policy cards (maybe in separate Equipment policy slots) which modify the Desirability for certain Equipment combinations, etc. Considering that production, stocking and supplying of equipment is a vital part of the mod, I'm thinking that changing the requesting and supplying behaviour through Desirability could potentially save/stop equipment from being issued and used unnecessarily.