2020 is in its final moments now and AOE1 DE by far only received 1 balance patch, which is great since it fixed all of the weakest civs and in some way nerfed the top tier ones, but still some tweak could be done here for units and civ bonuses:
Let me start:
General:
Melee Elephants trample damage blast radius and damage reduced.
Clubmen Line +1 LOS
Swordsmen line cost increased by +5 Food and 5 Gold
Greeks:
Give them Slingers and with bonus like firing 25% faster.
Minoans:
Replace that farm bonus to: Domestication, Plow and Irrigation upgrades for free
Extra range bonus straggered to +1 in Bronze and +2 In Iron Age and then affects all archers.
Persians:
Elephant speed bonus increased to 30%
Trirreme firing bonus applies to scout ship and war galley
New Bonus: Goverment center technologies cost -40%
Romans:
Lose Scythe Chariot
Receive War Elephant.
Shang:
New Bonus: Chariot Units move 10% faster.
Macedonians:
No longer get access to the Heavy Horse Archer
Receive Elephant Archer
The extra PA bonus of Academy units now includes Elephant Units.