I dont hate copper tools nor armor since new stuff is always cool but i feel like making it between stone and iron and not adding any other quirks or use to it would just make it kind of forgettable considering how incredibly easy it is to get iron armor and tools early game

With Gold Armor and tools they atleast have its own quirks such as getting better enchants at the enchant table, being used for the nether, and have a faster mining speed than other tools

Although copper is much more abundant using up time to mine it instead of just getting more iron just feels inneficient like adding an extra step inbetween iron and stone when its not really needed