Towers are mostly famous as a hated offensive weapon in Feudal and not as a useful defensive tool in Age of Empires 2.
As soon as you reach Castle Age you want to use your precious Stone on Castles and TCs and not Towers.
Castles provide very strong DPS, they give access to some of the strongest units (your UT and Trebuchets) as well as critical technologies (UTs and Conscription mostly).
The only Towers that see some usage in defence without massive civilisation bonuses (Korean, Japanese, etc.) are Bombard Towers.
How to make Towers strong in defence without making them strong in Offence?
One of the first things to make Tower rushes more manageable was increasing the damage of Villagers against Stone Defence from +3 to +6 in AoC 24 years ago.
My suggestion is to reduce the damage of Towers vs. Villagers by 2 the same way Shotel Warriors with Royal Heirs take 3 less damage by Mounted Units.
Villagers with Loom have 2 Pierce armour.
With that change the damage from Watch Towers (with Fletching) would change from 4 (5+1-2) to 2 (5+1-2-2) making them a lot weaker against villagers.
This change would basically not change the effectiveness of Towers in Defence since villagers are way to valuable to send to the enemy base in an offence in Feudal Age.
To improve Towers in their defensive role, especially in the late game, I would suggest following changes:
- Watch Towers get their full HP in Feudal Age again (850 → 1020)
- Tower cost from 35 W 125 S changed to 100 W 75 S
- Arrow Slits +3 attack for all Towers
The change to the HP is simply reverting them to their original state. This change was only done because Tower Rushing was too effective.
The cost change is designed to make them more affordable in Late Game.
In the early game Wood is a little “cheaper” then Stone since it collects faster, in the Late Game Stone runs out first and the market price can only go up. Making the Tower cost more Wood and less Stone makes them a lot more Affordable in the late game. Now one Castle costs over 8 Towers worth in Stone instead of just a little more then 5 Towers.
I changed the overall resource cost for Towers from 160 to 175 so they don’t become too cheap in the early game.
Also Towers did cost 175 resources until very recently.
This would also happen to be the same price the Slavs paid after researching Detinets.
The main potential balance issue I see is that players can make more towers with the starting Stone without mining any additional Stone.
But since towers do less damage against villagers that would be less exploitable.
Maybe it becomes more viable to build towers instead of walls in the early game.
The changes are not very big overall so I wouldn’t expect Towers to become super popular over night.
I thought about suggesting giving all Towers +1 attack but that would probably be a little too much.