Okay, just finished the game (Greece, The Great, Passive Tribes). The AI is generally better at conquering tribes and expanding. Rome even used some boats to hop the sea twice to create a chain of cities. By victory at 141 (cathedrals and holy sites ambition) there were still tribes in the furthest north tundra and on the island Rome was expanding too. Except for Egypt, much of whom I conquered at midgame, all AI empires have large standing armies of the typical axes, archers, conscripts, catapults. This game I notice Egypt pump out several war elephants, and others create some horsemen and horse archers. Rome also has some tier-1 uniques which they appear to have built in their capital with their empires only stronghold.
However, the main issues with AI development and advancement that I've described earlier still are in full effect. I'm surveying the map with revealfullmap after the victory.
- Rome and Assyria have all their workers actively building improvements, though Babylon has many idle workers. However, very few workers overall (looks like 1x per city) and this appears to have the effect that when AI build wonders, their main cities stop developing for 12+ turns. As a result, they are still upgrading resource tiles in the capital at turn 141.
- Very few civilian buildings, one Assyrian city has 2x courthouse and two Roman cities have 2x library, with a few scattered courthouses. Also, lots of windmills and baths (with master doctors!). Rome has 2x barracks in several cities.
- I see many cities running units/specialists/projects that will take forever to finish (9-turn specialists, 13-turn militia, a 24-turn settler, way to many disciples).
I suspect that all these together explain why the AI would advance so slowly. Again, I am surprised to see so many baths and windmills. Even an Egyptian city I captured at midgame had a cold bath, while we were still trading stones with slingers. And yet, I don't see any markets (and personally, until I get grocers I am just bleeding gold!).
Come to think of it, it would almost seem as if every AI empire draws a diagonal line on the tech tree and struggles to get any further: they research up to Hydraulics, Scholarship, Stirrups (sometimes), Architecture, Manor, Composite Bow, Monasticism, and Machinery. I don't see any units or buildings from any higher techs, which deprives them of all high tier units. At this point, I wonder if they get stuck researching techs like Jurisprudence, Lateen Sail, and Fiscal Policy which would easily shut down their research through the endgame. Or if they grab too many of the Discover Bonuses along the way (the only ones I consider are free settler and discontent reduction, some earlier courtiers would be tempting).
If any game updates or mods were going to strengthen the AI, I think the following changes would be important:
- Change the formula for number of workers. I end up with about half the numbers of workers as I have orders, which lets me flex from building to combat pretty effectively and get all civilian buildings soon after they become available, alongside carpeting rural improvements. It looks like AI are coded to start each new city with a worker (and presumably to replace killed workers), but getting a second/third in the capital and a second in most other cities would go a long way.
- Only build civilian units in high-growth cities. Settlers and disciples bog down cities, and militia are only worthwhile if trained quickly.
- Give the AI some kind of city classification, e.g., training, urban, rural. Prioritize military and officers in training cities, civics followed by specialists in urban cities, and resource specialists in rural cities. Projects should probably only be run if civics are high or no other good options exist. Monks are very good, and can probably be prioritized in both urban and rural cities.
- Increase weight for techs that unlock new units and civilian buildings. Lower the priority for baths and windmills, as these are not that useful until an economy is in place.
- If the AI rush things, I would recommend weighting the decision to rush on how many turns it would save the city multiplied by the target value of that city's main yield. The goal here is not to waste a training city's turns by training officers, or an urban city's turns developing its first few civics boosters.
- Prioritize strongholds, citadels and unique units in the 1-2 cities with the highest training.
Even just hardcoding different weights for techs and increasing the number of workers might be enough. The AI would then probably tend to distribute their military and civilian production across all cities, which is not optimal, but at least overall production would be about twice as strong as it is currently with adequate resources and all civilian buildings built.
If the AI gets high-tier units, it may become important to change the formula for what rebel units can form. As soon as I get crossbows, all my rebels are crossbows, before I get a chance to even build more than one. This would decimate the AI's standing army.
I'd love to hear how feasible any of those improvements may be to mod. I've mostly just changed around parameters values in Civ6 and am interested at trying my hand at some simple mods in OW. Are there any AI-only autoplay options for testing mods yet?