i play 31 civs on a tiny map, usign the ditor to add civs. its really funny, cassue on the second tun, there is no gaps in culture, so it is basically luck if you get a good starting place, you build 3 or 4 units, kill a few civs, then you suddenly become 3 times bigger than anyone else, which basically means you can control the game because you can build so much more than the AI can and take over huge amounts of civs in a very short time. although if that first war goes wrong, then it is a real challenge to stop the dominate 1 or 2 civs.
however, normal games i play are often large map, 10 civs. nice balance between empire building and close quarters early war.