Honestly this is all just disappointing.
Stone age tools are practically tutorial items, these are the @%$*#! you are getting for the start of the game and you are supposed to ditch them as fast as possible.
Heres how i think the game should progress:
- Really early game: Stone and Brass age
So the player starts out and gets itself some stones, wood and fibers and makes a stone axe to start crafting. They continue this as long as they learn to make a Forge or have enough materials for a Primitive Forge ( its a bunch of stone and clay cobbled together and can only make brass ).
Once they have somekind of forge they can collect brass to enter the next age (what historically also makes sense). They get their tools all replaced by brass tools, durability is still low but they got much faster and more efficient tools to work with
- Middle game: Iron and Steel Age
The player is running around with brass hammers and spears collecting whatever they need to advance into iron age. They make a forge and start smelting iron and steel, this is the longest period of the game with loads of different equipment.
- End game: Specialized equipment
At this stage the player most likely figured out what and how they like to play, at this stage i would like to see somekind of "engineers table" or "advanced forge" where you can make specialized items for your style.
If you are stealthy you could make a ghillie suit what decreases zombie detection range and makes no noise or if you liked to use bows you could craft advanced recurve or compound bows with much higher range and damage than their normal counterparts.
Essentially this is the stage where you specialize in what you like and you also need the upgrades from here because the game is getting more and more dangerous.