The primary reason for iron weaponry supplanting bronze isn't actually that it made better weapons, but rather it was more economical. Bronze is made up of both copper and tin, two metals which were not usually found together. Large bronze-armed forces required a vast, interconnected trade network of miners, metallurgists, smiths, and other artisans. This wasn't a problem prior to the Bronze Age Collapse around 1200 BCE, when civilizations around the eastern Mediterranean suddenly and completely imploded, cutting off the trade networks vital for bronze production. Iron, once discovered, did not require this delicate balancing act, and so filled the void.

Bronze is also much easier work with, lending itself more complex forms, as well as being much easier to repair. It holds an edge better than iron and doesn't rust, and therefore being MUCH easier to maintain.

Iron, in addition to being more economical, is somewhat heavier, and can provide a stronger point of impact when used correctly. It is also a bit harder, and usually won't get bent out of shape after a long day of hacking at one's enemies.