I just played most of what is probably my best. Was ahead of your chieftan time for quite awhile, but after two AA SGLs I never got another one and your cpt overtook mine. In 900 AD, I am still ahead in overall culture, but cannot keep up. I'll probably go for a few more techs, and if no SGL will give it up, as 1360 or 1365 will not be acceptable to me.
After this game, I think I am going to try a different method. Instead of tiny, low diff, Babylon, I will start on huge, high diff, and the Arabs. No worries about SGLs or anything, which is the way I like it.
Or, maybe I will just generate completely random starts on all different map sizes, and tailor the victory condition to map, as even my sporadic 20k attempts become frustrating when I continually fall a turn or two short of your game.