Would bronze tools not be better in the long run? They still need to be sharpened but not as regularly as copper would be. Or was bronze too precious a material to use for just regular tools as opposed to like weapons and armour?

They also used bronze tools. Copper in Egypt contains natural arsenic, which makes it harder than copper elsewhere. Bronze, however, despite small objects being produced from the 2nd Dynasty onwards, did not come into common use as tools until the New Kingdom.