My setup:
- Single player treaty 40 game against one AI opponent on sandbox difficulty
- Map was Amazonia to have as few AI interaction as possible
- Use of cheats to get age up fast/get ressources/build 80 villagers
- Put 40 vills on mills + 40 vills on coin
- Start at "35 minutes remaining", end at "15 minutes remaining"
- Checked how many ressources I had at starting point and end point
- No upgrade cards/upgrades in the buildings themselves
Result:
- In 20 minutes game time, 22.486 food and 17.028 gold were gathered by 40 villagers each
- This translates to (rounded) real base gather rates of 0.468 food/sec per villager and 0.355 gold/sec per villager
Please not that gather rates on rice paddies are 0.5 food/sec per villager and 0.34 gold/sec per villager. As villagers do not walk around on rice paddies, this number is already correct. Unupgraded rice paddies are ~7% better than unupgraded mills, while they are ~4% weaker than unupgraded plantations.
I did not test having just 7 vills per mill/plantation. If anyone bothers to find out, just post it here and I will put it to the results (with a reference to the fellow player ofcourse).
Now the interesting question is: whose countries villagers have the potential to be the strongest?
Let's take a look at some examples.
Japan
Japan has lots of upgrade home city cards for rice paddy gather rates. They add up to +81% faster gathering of food and +121% faster gathering of coin. Rice paddy upgrades themselves add a further +95% and + 120% respectively. Hence, fully upgraded japanese villagers on rice paddies will gather ~1.38 food/sec and ~1.16 gold/sec.
Russia
As far as I know, Russia has all european upgrade cards for mills/plantations (+ Economic Theory). They add up to +60% faster gathering of food and +100% faster gathering of coin. Mill and plantation upgrades add a further +95% and +110%. Hence, fully upgraded russian villagers on mills/plantations will gather ~1.19 food/sec and 1.10 gold/sec.
India
India is one of the countries with relatively few upgrade cards. They add up to +30% faster gathering of food and +45% faster gathering of gold. Rice paddy upgrades again add a further +95% and +120% respectively. Hence, fully upgraded indian villagers on rice paddies will gather 1.12 food/sec and 0.9 gold/sec. Additionally, indian villagers get a +10% bonus for being close to Karni Mata which yields 1.21 food/sec amd 0.99 gold/sec for each villager.
European/Asian without upgrade cards
A european country without any upgrade cards from HC but all upgrade at the mill/plantation themselves will gather 0.91 food/sec and 0.74 gold/sec. An asian country without any upgrade cards from HC but all upgrades at the rice paddy will gather 0.975 food/sec and 0.75 gold/sec.
That leaves fully upgraded japanese villagers being
- ~16% faster at gathering food and ~5% faster at gathering gold than fully upgraded russian villagers
- ~14%/~17% faster than fully upgraded indian villagers close to Karni Mata
- ~50%/~56% faster than european villagers with all mill/plantation upgrades but without HC cards
- ~42%/~55% faster than asian villagers with all rice paddy upgrades but without HC cards