So, I slept on it overnight and decided to take a different route.
I reverted to an earlier save, the one with 1 turn to Oracle completion, and bulbed mathematics. I then researched Calendar for Silk and Incense. In the interim I sent out 4-5 (can't remember exactly) and with one of them I settled the beaver.
After that I went Alphabet - HBR, but no AI has anything to trade really. Capac was going for all the religious and art techs I think, He founded Hinduism, Confucianism and Christianity and spread them all to me. In the end I spread Buddhism, and went Buddhist cos I knew I was going to declare on him and didn't want brothers and sisters of the faith unhappiness.
Long story short, I built libraries and gers nearly everywhere, over-produced Keshiks and took 4 of his 5 cities (one I razed). He's not really improved anything except farming flood plains, 1 iron and about 6 wineries. No hills improved at all.
I've scouted out both Fred and Sitting Bull and they are very similar.
Winning this will be pretty easy now and, to be honest, I think it's time to move on and maybe try a new scenario at Noble lvl.
What do you think?
Save is attached. I've probably made a few mistakes. Screen-shots can be uploaded if you would like to see them.