I did mention that they should be limited to Arab nations “during the Bronze Age”. The camel was only used extensively (as far as current research shows) during the Iron Age, which started c.1200.
The first recorded use of a camel in battle is from 853BC, during the Battle of Qarqar. (quickly googled it as i couldn’t remember everyone involved. heres a link - https://en.wikipedia.org/wiki/Camel_cavalry) An Arab king fought against the Assyrian Shalmaneser III with about a thousand camels. It’s not clear who won, or exactly how they were used. And this Arab king could be associated with an Aramean king known from the Bible.
After this the only real evidence we have is from the Lydian battle you mentioned, Which was Late-Iron age.
So, historically speaking, having any camel in your army pre-Iron age is sketchy at best.
In fact, Egypt didn’t have camels until about the 3rd century AD (see here, you may have to log in https://www.jstor.org/stable/542916?seq=1).
I would therefore scrap Camels completely from the game and add them as an iron age elite unit. Personally, i also feel that we need an extra age. The amount of nations in the game creates a massive scope, running from before 3500BC all the way to c. 100AD.
Nations like the Romans didn’t develop much before c. 500BC (Rome was only built c. 753BC), which means that having them powerful in the Bronze age is ridiculous. This applies to units as well. “legion” is a military term used almost exclusively for Roman armies during the Hellenistic period, just as Hoplite was a unit only used in Greek armies, with Phalanx being a formation of Hoplites that interlocked their shields to form a wall of shields with spears sticking out.
Having nations that never even heard of hoplites build them in-game is also a bit of a stretch, though one can maybe assume that this represents the Hellenistic era. Which brings me to the “new” age i feel should be included.
Warfare before the Alexandrian invasion in 336/335BC was very different to what it became after it. Greek styles of weaponry, formations and army types were introduced.
So i propose that the iron age limits it’s units and technologies to 400BC. They can expand on the tech tree, making powerful units that are representative of the time (as most units are). They should also add a bantering ram as siege equipment and remove the ballista. Wars and sieges were won with slingers, compound bowmen, supported by chariots and horsemen (mostly scouts, so lose the cavalry unit for most nations except persia). Egyptian Pikemen were feared during the late bronze and Early Iron age, so add them in, change the model of the longswordsman to something similar to the short-swordsman, just dressed in whatever nation’s clothes you are (robes and turbans for Mesopotamians, bare top and kilt for Canaanite nations, Egyptian style for Egyptians) . Remove the Greek hoplites and ballista-type weapons and keep the stone thrower un-upgradable.
Then, in the new Hellenestic age add in the Roman Legionaire, Greek Hoplite, Cataphracts (also not something seen before c. 300BC), the trireme, all the siege ballistas and towers, flame ships and whatnot.
Sorry this was a bit of a ramble - was replying and went off on a tangent, will add a properly curated list when i have time.