The ability to grab ammo or health packs from the backs of players. It is endlessly frustrating when you're begging someone for health or ammo (usually ammo) and they just straight up ignore you. It'd be great if there was an additional "pack slot" on the back of these classes that anyone on the same team can grab and drop on the ground (only one at any given time). This way uncooperative players can't block their team from getting the support they're supposed to providing.