lurker's comment: Just a couple of comments:
a. Food is a bit hard to come by, but production is also very important. Settling on a hill is a good idea. Your starting 'settler' treats all terrain as road and move 2 tiles/turn. It's ok to move a couple of tiles to get some good terrain (floodplains and hills make up one of the best starts in Chiefdom, imo).
b. Grassland isn't the greatest all by itself. It can only be irrigated (but not until the middle ages), and it only gives 2 food in Chiefdom (sort of an equivalent of Despotism). Grassland irrigated with some hills or other production terrain can be good, though.
c. Dynasticism is very important. Getting out of Chiefdom and into Monarchy is a good first step. You could wait later for Democracy or Republic (a couple of techs away each), but for me, I like to switch asap.
d. The AI is much more agressive. If you settle a town close to them with no defense, chances are they will come by and declare war unprovoked. Barbarians do keep them occupied, like DocT stated.
e. Some improvements, like worker housing become obsolete in the beginning of the Middle Ages - just watch out for this.
f. Some resources like Incense, Gold, and Ivory (Elephants) are now strategic - that means they can deplete! Don't connect Ivory until you research Elephant Training if you can afford it. And don't connect more than one source of each unless it's to trade just in case they deplete.
g. Your scouts can pop barbarians from a hut if you're not expansionist, so beware (because they would then die).
Other than that, I'll keep watching. I'm in the middle of my first true RaR attempt as the Celts on Monarch and I have 50% of population and 20% of land in the middle ages. Good luck!
- Watch out for the Horses!
