Back to the question which civs work best with liberty:
Basically, you want to spam a lot of cities, so your civ should be able to combat the disadvantages of spamming cities
What are those disadvantages?
1) Gold per turn - you need a lot of expensive infrastructure like monuments, shrines, libraries etc. before you get to markets
2) Lack of production - cities remain small and you want to be able to maximize production with as few citizens as possible
3) Negative Happiness = no growth - certainly the biggest limiting factor
4) The AI will get mad at you - defense can be very difficult
5) Culture - Costs per policy increase a lot per city so the more culture the better
6) Religion - very flexible and can negate 1-2 problems
So yeah, which civs can counter these disadvantages with their UA, UB and UU (best per category)?
Money:
Inca or
Carthage, without a doubt. With Inca, you save 1 gpt per free road on hills which is extremely strong and easily beats Arabia in the early game. Just build enough workers to get your road network up and running asap. Carthage gets free trade routes between coastal cities.
Production:
I'd say
Russia or
Rome. Extra hammers are very important to get the essential buildings in every city. Russia also has the additional advantage of selling a shedload of horses to the AI for extra cash.
Happiness:
Believe it or not but I'd say
Egypt. +2 happiness per burial tomb is awesome. Take the piety opener as well for faster production.
Defense:
Everyone with an early UU. UUs can certainly help but aren't the most critical factor.
Culture:
France, obviously. Followed by
Polynesia with Moais - they can also settle on islands immediately and grab a lot of luxuries.
Religion:
The
Celts and
Mayans
Others:
America also works well because they have the best scouts for good city locations and can purchase important tiles with less gold.
Final list: Inca, Carthage, Russia, Rome, Egypt, France, Polynesia, Celts, Maya, America
I feel like I'm missing someone here but it doesn't really matter