Bronze items are like iron, only more durable.
Except bronze armor, which is incredibly OP, having the protection of diamond.
And why is it OP? Because, bronze is relatively* cheap, , and while diamond armor last a lot more, very few can afford to spend 24 diamonds to make armor, even if they have significantly more than that, so naturally bronze armor is much earlier game item.
And for those saying that it's a small upgrade from iron armor, iron armor has 60% protection, while diamond one has 80% protection- that halves the damage you receive, for a material that even in the most intensive game environment requires at most 1.5 copper, 0.5 tin, and a macerator set up to make (which is a point long before most have even 5-8 diamonds, much less 24 spare diamonds).
Of course, going back from the first sentence, the suggestion here is to make bronze armor similar to the tools- iron level, but more durable.
*if you take other mods to account, it's even more absurdly cheap, but since here if it's not The Holy GT version of Balance (registered trademark of Gregorius intergalactics) it's WRONG!!! so i won't even go on how it messes up the balance in a mod-environment with other common-to-very-well-regarded mods (including basically any mod that adds either bronze or dusts) .