I don't think Classical Era (age) is need here. i prefer Exploration Age being 3rd and Modern being 4th. or elongating those three ages thereof.
Age II unit rosters are very off to me. especially when it comes to navy. player always begin with cogs while IRL first 'cogs' only shown up by the waning days of 10th Century AD. and cogs aren't really first choice warships. but instead militarized civilian vessels. and did not replace galleys until quite later (1340 at Sluys). before that there are variety of medieval galleys, even in Europe there are two shipbuilding traditions
- Mediterranean. a seemingly seamless traditions from the antiquity dated back to 12th Century BC (Egyptians and Phoenicians in particular), though much of the Mediterranean shipbuldings that survived well into the middle ages stemmed from 3rd Century simplifications. (Great Plague of 3rd Century Crisis claimed roughtly one third of the Roman population. among those were shipbuilding workforce which were all skilled craftsmen and not just any unskilled workers, this shortcoming is one of may reasons that ship designs of the Late Roman Empire became simplified. and not much is changed)
- North Atlantic Traditions.. or 'Clinkers'. it is said that this one is also old, originated from sewn boats. and even Julius Caesar himself used Venetii clinker ships to cross English Channel to invade Britannia.
Cogs were originally made with Northern Traditions.
Back to List of units in Civ7 The Cog is an Exploration Age tier 1 naval unit in Civilization VII. In the Middle Ages, trade routes dominated by the Hanseatic League crossed the Baltic and North Seas (and cautiously delved into the Atlantic Ocean). Their ship of choice was the cog, a slightly...
civilization.fandom.com
Also Duke William II of Normandy invaded England with clinker galleys being his transports of choice.