I think there should be a high/low mix, and the commander on the ground should decide which to use.
Low mix would just be a 5 layer Rusar uniform consisting of pants and a jacket, gloves, armored boot bottoms, and hard shell helm with a neck skirt. Purpose of the low mix is to be used in rural areas, where the main danger is from artillery shell fragments, land mines and flames. Countermeasure to guns is just taking proper cover.
High mix would include a chest rig and general full body armor on top of the low mix, also including a gun shield. To be used in areas with lots of corridors and doors to be breached, such as urban areas or breaching of bases and ships. Cover might not be possible in such areas, so heavy armor is needed.
Either way you can encourage your commanders to stay in the rural areas as much as possible to decrease costs, but in the end it has to be up to the guy at the frontline to decide what to use.