Arabia 24
Aztec 4
Babylon 24
Carthage 22
China 25
England 17
Ethiopia 10
Greece 15
Inca 31
Iroquois 10
Korea 26
Maya 24
Netherlands 19
Persia 18
Roman Empire 15
Russia 11
Siam 17
Upvoting Babylon again. In my eyes they will always be the best science civ, with the best chances on the highest difficulties - and doing it very early at that. T230 Babylon win is very likely. As for the people who dislike their UU and UB, I will repeat myself for the fourth time - what do you expect from a civ that was formed around 3500 BC and assimilated/destroyed by others by 141 BC? A Mothership UU and Deathray Tower UB? Almost everything at that time was swords, spears, bows, arrows, horses and chariots (last 2 being kinda rare - the Archers, Pikemen and Swordsmen ruled the battlefields).
The best advantage of Babylon is the early Renaissance rush, while almost all other science civs need to expand first to get the science going. Just play OCC at start and beeline Education, then go Sailing - Optics - Compass and use Oxford for Astronomy. If you settled next to a mountain (which you should always do), get the Observatory, and now go all out expansion. Even if you have to get construction in the meantime for defense with CB's, cause you got DoW'ed you can still achieve it under T100 in any game. What's better, you never get beat to Petra (wicked desert growth), Oracle (GS point), Pisa and PT unless Rammesses is in the game, and is allowed to advance without interference.
For a third week in a row, I am still not convinced that Korea is better than Babylon. With a 4-city opening on Deity, you face a number of problems: 1. Happiness. 2. Very late NC building which lasts a long time due to having more cities (1 city with good production builds it in 5-8 turns). 3. Varying extra BPT from Rationalism unless you stop the growth in your cities just to keep happiness of 1 or more. 4. Takes time to get Universities in the tertiary cities to finally go all out science and hampers the Oxford Uni creation. 5. You get beat to key wonders, like GL, ToA, HG, Petra, Pisa and PT (!!!) almost every time, unless you have AI opponents that care little about wonder building. 6. What is the 1500 BPT in the end of the game good for when you win the Science victory like 30-40 turns after Babylon?
Granted, my failures with Korea on Deity may be due to the fact that I am not so used to playing (or just plain suck) with them. I will look for different options, but so far few things outweigh the usefulness of a planted GS boosted by +50% from NC and +50% from Observatory, along with a capital of 16+ upon entering Renaissance, and a happy nation for 15% more BPT.