When firearms started showing up armor was discarded because it was largely ineffective against bullets.
This is not correct. Armor is far more effective against firearm projectiles than no armor.
After the widespread adoption of handheld firearms in European warfare, armor simply became cost-inefficient. The "Military Revolution" historians - Michael Roberts, Geoff Parker, and their epigones - have shown that chemical explosive projectile weapons necessitated a humongous increase in rulers' military establishments. Only the new "Italian trace" fortification style could stand up against bombardment, and such fortresses required an exponentially larger garrison. Any attempt to
besiege such places would also require more men. The "Military Revolution" hypothesis argued that the financial and bureaucratic power necessary to mobilize and supply these larger armies contributed dramatically to centralized state formation. But Parker in particular has also argued that even with the improvements in banking, governance, logistics, and suchlike things, the new armies of the sixteenth and seventeenth centuries were too small to meet requirements.
Costs had to be defrayed somehow. Sometimes that meant cutting armor issue in favor of uniforms and small arms; other times, it meant imposing new financial duties and restrictions on the aristocratic warriors who had once been able to supply their own armoring.
Yet even these measures were incremental; they did not cause the disappearance of body armor altogether. Into the early sixteenth century, many infantrymen still made use of some protection, usually around the chest, though this slowly disappeared by about 1650. But even after that, almost all European armies continued to maintain heavy cavalry units, often classified as cuirassiers after the metal protection they donned. Cuirassiers and other heavy armored cavalry were not made obsolete by firearms. Instead, they kept their role all the way up to the late nineteenth century, and participated decisively in some of the era's most famous battles. Imagine the Battle of Vienna (1683) without Poland-Lithuania's armored "Winged Hussars".
In addition to employing metal body armor, cuirassier regiments would act very much like their knightly ancestors. They would be largely comprised of noblemen, many of whom could buy their own gear or at least defray the cost to the state of providing it. They would maintain an aristocratic ethos and code of conduct, and as a result their social standing would be near the top of an army's pyramid.
There are other, scattered examples from history to show that metal body armor was far from useless against bullets: the last stand of the Australian outlaw Ned Kelly, for instance. It was simply beyond the financial and practical means of states of the time to armor
everybody. And no state in world history has seriously tried to armor
everybody anyway.
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On-topic, I would like Cassandra to be armed with a proper flail.