Right now, in order to mine quality you're always forced back to mining with the stone axe. This feels bad from a progression point of view, being forced to use the first tool you make when you have 500 strength and can smash layers 1-4 like butter. It looks bad from an animation point of view. And it feels bad because of how incredibly slow you mine with it.
Actual example for previous gen qualities: Q113 pickaxe, Q160 stone axe, Q135 Anvil set, Q140 metal, Q105 branch
Suggestion: Prospector's Pick, Any metal + stick, crafted on anvil.
Quality in this scenario: (((105+140)/2)*9 + 135*7)/16 = 127.9 prospector's pick
In order to make this new item optimal, nerf the stone axe to be 75% effective quality for mining, and give the prospector's pick 125% effective quality. This would give Q113 pick, Q120 stone axe, Q159.9 prospector pick for the effective mining quality. A small speed boost might not be bad, but I think this would still "feel" better from a psychology point of view.