As Arma 3 seems to aim toward even more flexibilty than previous installments, it would be nice to extend this to the AI too.
Currently the main difference between AI units is their skill levels. AI behaviour can be customed with scripting and mods, but the problem remains that all AI act pretty much the same, which is bad.
Different fighting forces use different tactics and react diffently in the battlefield, depending on equipment, opposition, training, morale etc. All this is impossible to simulate completely. However, editable modules for different tacticts can help simulate differences.
Say that a mission maker wants to have the player/s Special Forces unit support a small number of regular conscript army units plus un-trained civilian militia. The opfor is an undiciplined, but fanatical mob supported by highly skilled sniper unit, who is the players main target. These are basically five very different units. With one AI thei all tend to act the same and the mission won't work, however.
With different AI modules linked to each unit, their behaviour and skill levels could be set individually for each unit (or, in theory, even individual fighter). Spec For for players unit AI, conscript, militia, mob and sniper. The modules could be customised and mixed with scripted moves activated by Triggers.
Done properly this would result in very detailed and dynamic missions. Also, AI modules would enable a way to recreate period and national tactics from WWII and other mods, as well as more varied behaviour for civilian units (and zombies :) )
<Edit: Almost forgot> Modular AI could be used for better tank, helicopter and Aircraft AI, which are currently rather simplistic.
