I've found that one of the more disappointing restrictions imposed on ARMA 3 is the inability to use enemy uniforms. While I acknowledge the Hague Conventions prohibit the use of enemy uniforms in war, international law is not always followed, especially in the context of paramilitary special operations.
If uniform restrictions were made a mission variable, it would open the door to more creative missions and ethical quagmires in which players can choose their own paths.