I think it would be useful to highlight nearby friendly ammo boxes with icons, at least under some situations. For instance, an icon could float over them for players who have requested ammo recently, or for players who are out of ammo for one of their weapons (this would make it more intuitive for new players who don't know about the request button -- WHERE I FIND AMMOZ? Right there.) Also, it would help players find ammo boxes on unfamiliar maps, which I think is good, and would help them notice if the comm has dropped an armory or if an engineer has dropped a box. Maybe also highlight them on the map under the listed circumstances, although that's a bit less useful.