So you want a system that accounts for weight, but then want these materials to be weightless............
If you are going to request a system that accounts for weight, everything has to have a weight. Bullets, duke casino coins, vehicles, stones, iron ore, etc etc.
Sure, it is within devs reach if they want to overhaul the entire system and go back to scratch. Then they have to add weights to all objects, add additional items to handle the weight, reconfigure SI so now it has to take into account for weight (so when a survivor dumps a ton of ore into a chest, the floor caves in on them). Throw in all the trips back and forth to the mine to haul materials to your vehicle, then from your vehicle to your base because realistically you can only haul about 50 or so lbs at a time.
I am fine with the system as it is today, I don't think they need to start all over. If this game was still in the planning stage, sure it could be considered. But asking the devs to go to a different storage / item system at Alpha 20 (when the game is close to going gold) is a bit of a stretch in my opinion.