I was curious to see how vanilla C3C with only the following modifications turned out (using the default 'Quick Civ' biq file.
- turns increased back to 540
- no AI starting units
- AI Cost Factor is the from the next highest difficulty
- modifications to world tech rate for small & standard and modifications
- 30% of land and population for domination victory
- settings optimised for tiny 60% water, small and standard on 80% water
I picked 6 Civ, small, 80% water, continents with random land.
I was Celts and did rubbish (crap starting land with only fresh water on the other side of a vast swamp, locked in by New York immediately and America gets Great Wall and Statue of Zeus, so early war didn't look a great option - then turns out I am furthest away from any islands, so just played to experiment).
This is a one off game, so I would not draw firm conclusions but what I found in this one game was:
i) Fairly even expansion phase (expected)
ii) No snowballing by the AI despite no intervention from me - so the AI didn't get near the 30% domination win condition (not expected, but far away continent had 3x less aggressive Civs)
iii) Less AI aggression against each other (perhaps due to the even expansion phase, so no major differencies in military sizes)
iv) AI could have got a OCC culture victory if I had kept playing - having got to 15k in Istanbul (not expected - so perhaps this AI OCC push is tied somehow to removing the starting AI units? Zero culture tweaks by me with these settings)
v) got to 1970 AD in 1hr 40 mins. So this really does produce quick games (although the 'Quick Civ' biq lets you tech in 1 turn and speeds up worker moves).
Conclusions
1) I much prefer this type of expansion phase to the vanilla settings.
2) the 'Quick Civ' settings do permit a genuine under 4hr gaming experience (it is a shame people don't seem to do this as a full game multiplayer).
Note: I forgot to make domination 30% in the game I played, but that is corrected in the attached biq.