Just wanted to give a preview on my tactics in C3C tiny Sid -
I ran mapfinder searching for a river to grow a large city on, and to have the agricultural extra food.
My plan is to grow to size 6/7, and only then enter a GA.
There are a few ways to do this, but I need to wait for the city size for the GA to be effective enough at Sid.
Another aspect is to trade Bronze working soon, and receive Iron working after the first war.
I can't gather enough money for mass upgrades, but 2-4 warriors/JAGs can be upgraded to sowrdsmen.
Since I can't upgrade all, I start producing archers and 1-2 spearmen early, and use some kind of SoD to take cities.
I build usually 1-2 JAGs only for the GA - spearmen/archers are better, and there are many spearmen to fight.
I have thought if I can "surprise attack" 2 nations together at Sid, but it seems pointless.
The settler advancement of the AI is too great, and dealing with 2 AIs in war is not an option.
I could hurt them both, but not enough for me to get on my feet and continue.
So, I have succeeded in eliminating the Americans once in 1910BC, but failed to attack the French effectively that game.
In any case - destroying one AI and then go to surprise the other seem to be the correct tactic.
Another serious problem I encounter is that the settlers start to go by sea at about 2000BC, and empty places are being reoccupied, forcing me to keep forces all over the map.
This fact, and the fact that the world is tiny and I always lack forces when my GA finishes makes me believe that the solution must be creating more cities, instead of relying only on my capital.
I do sometimes capture cities, but they are sometimes abndoned a few turns later (causing C3C to crash thereafter

).
So, in short, kill first AI while expanding, then amass all that's left to make a surprise blow to the second, even if it makes me wait 2000 years. (I am jewish, ya know!

)