It is the best if Microsoft make only ONE big Update, because if they make an update every week or every month, at Multiplayer game is very OFTEN if some of the players have NOT the last update, so the game CRUSH, CRASH, after few minutes.
Also, it is better if the game is Historicaly accurate. So some civs will have advantage at Dark, or at Feudal or at Imperial age. For Example for the Period or Age of Empires 2, the Huns, Byzantines, Persians and Chinese may have advantage at Dark and Feudal Age. The Bulgarians will have advantage at Feudal and Castle age. The Saracenes may have advantage at Castle age. The Turks may receive some advantage at Imperial age if they have much gold. The Mongols have all upgrades at Imperial age. The Spanish also will be weak at Dark and Feudal age, but they must receive advantage at Imperial age. The Mongols were the most powerful civ at the End of the Period of Aoe 2- about 1400- 1500 AD…
Also, all elephants must be build at Castles, because you may read the History. The Horse soldiers were much more than the Soldiers over elephants. When 30 000 Mongols attacked Khwarazm( Khwarezmia ) the fought against 150 elephants.
So some civs may have Trebuchets and bombard towers, but other will have not it.
The Rajas kingdoms reached only Castle age. The Africans reached only Feudal age and they did not used Trebuchets or Bombard towers.
It is Normal if Chinese have advantage at Land Nomad map.
Otherwise, the game become as a fictional game. And it would NOT need to write any History files in it. As somebody eat Narcotics and go -committing suicide.