A note on the Iron - Steel - Bronze debate.
The primary characteristic of bronze was that it was always, everywhere, Expensive. Copper and Tin, the primary components (although arsenical ores were used for a less-effective form of arsenical bronze very early, and Roman 'Bronze" was actually usually made with Zinc, so was correctly Brass) are rarely found together, and so bronze required at least one or more long trade routes, with frequently very few or no alternatives - which means that the traders could jack up the prices with impunity, and did.
Bronze was the first metal strong enough to be an attractive alternative to stone: copper tools were earlier, but, for instance, in North America natives were exploiting major copper deposits for thousands of years, and trading copper and tools from it all the way across the continent from the Great Lakes to Florida, but they seem to have been as much 'prestige' items more than useful tools. They stopped exploiting the copper deposits long before Europeans arrived, because copper tools were not as handy as those made from stone or obsidian!
Bronze is directly responsible for some other technological developments: it was the first metal that swords could be made from (although, to be precise, they were what today would be called 'short swords' averaging .5 to .7 meters long) - an entirely new type of weapon compared to the earlier axes, stone-headed maces and clubs, or flint-tipped spears that seem to have predominated in Neolithic melee warfare. Bronze toothed saws, that allowed clean cuts to be made across the grain of wood, always appear at virtually the same time that solid wooden wheels appear - because a solid wooden wheel requires cuts across the grain to be strong enough to support any weight, so, Bronze Working and The Wheel are directly related as technologies.
Bronze is actually stronger in many ways than wrought iron, but some of this is due to a thousand years or more of bronze working in which the techniques were refined compared to primitive iron working. Also, there is now some question as to just how primitive the early iron-working was: metallurgical analysis of some early Hallstadt iron swords (proto-Celts) showed some of them to be mild steel or close to it, rather than strictly 'wrought iron'. Quality control, as always in pre-modern technology, was critical: you could never be entirely sure just how good your 'iron' sword was until you tried it out, but the fact that some were much better than others in practice is attested by the number of legends about 'magical' swords from all parts of the world.
The occasional 'super sword' of iron was not as important as the primary characteristic of iron, which was that the metal ores are available almost everywhere - at least in the small quantities used in pre-industrial times. That meant as soon as the technology to work it (higher-temperature kilns/furnaces, so Iron Working is related to Stoneware Pottery, which used the same technologies) was developed, Everybody could potentially have iron tools or weapons.
That means, while Bronze is an aristocratic metal, only affordable by the rich and few (see Homer's Illiad, where the Heroic Warriors are the ones in bronze armor and with bronze swords), Iron was the Proletarian Metal, affordable by a new 'middle class' of land-owning farmers. That, in turn, meant a whole new type of army: amateur farmers well-equipped with iron weapons like iron-tipped Hoplite spears or link mail iron armor and iron swords on the earliest Roman Legionaries, or masses of Celtic warriors with iron swords and spears. That meant that Iron changed not only armies, but Cultures: the Heroic Aristocrat had to find a new calling or be overwhelmed, so enter the aristocratic General replacing the aristocratic warrior - a least until feudalism revived him.
Just from this little metallurgical essay it is obvious that Bronze and Iron technologies have direct consequences for other technologies (The Wheel, Advanced Pottery) and cultural/social policies (Heroic Warriors, governments like Aristocracies, Oligarchies, Democracies, effective 'militias' like Hoplites and early Legions, etc).
Anything as comprehensive as the effects of Iron tools and weapons or Bronze availability did, and should have in the game, effects on a range of other things: other tech developments, social policy, politics, civil structure, culture . . .
