I like how we're finally talking about properly balancing stack sizes. balance all depends on how much MM wants his game to be realistic or just fun. Because if you were to go full realistic mode then we would be only able to carry 20-50 small stones and 10-25 raw iron chunks before you could not carry anymore let alone carry a 4x4 jeep in your pocket. I myself fully understand that I can't in real life that is carry 20 stacks of 6000 small rocks lol. 7D2D is a survival game that tries to have alot of common sense elements to challenge your character to survive. from my experience of the game it is not an inventory management game, its a game where you are suppose to loot, build, fight, defend and above all survive. If you die your char should lose something permanently that you have to then redo or reattain (another topic but Death needs to be punishing)
If you go the full realistic mode for loot stack sizes then you severely diminish the core function of the game and would have to change subtitle to the game. from "The Survival Horde Crafting Game" to "The Survival Inventory Management Game"
For example all building materials like rocks, iron, cement, wet cement, gas, lead, brass, and any other raw materials the stack size should all be set at 3k IMO this is to make it uniform while at the same time reduce the amount of material a person could carry as it would demonstrate a "sense of realism" without killing the crafting theme of the game. Also maybe have it to where when you put those items into a storage container the stack size is doubled or tripled? IDK? some other games do this like Empryion and to me that makes perfect sense.
this is just an example of just the raw materials. have them at 3k on the person but 6k or 12k even when put in a container
hope this is somewhat helpful or insightful. Overall 17.3 is amazing great work TFP!!!