First spoiler is
here.
I'm quite surprised I was able to finish this game, the small map helped a lot. I had started it in early July, but played from 250BC to the end in three sessions, July29/30/31, submitting a few hours before deadline.
However, even a greater surprise was that I was able to actually win the game, and compared to other spoilers here, it looks like my result wasn't too bad. I think the advice I got from
RobertTheBruce and
Balbes 
to a comment with a screenshot I posted in the 1st spoiler thread was decisive to my success.
I was in 125AD, had finished Roos and while MM's cities were closer, he had more troops in them, so I decided to attack Gandhi instead. I had a good stack with many cats but it still lacked WE's for defense against Gandhi's HA's. Following RTB's advice, I waited another 10 turns to reinforce before attacking in 375AD.
Took and kept 2 cities (Pyramids in one of them), 10 turns of peace then war again until 1170AD. During this period I took and kept all his cities in the subcontinent. Unfortunately, getting peace from me was not enough to save Gandhi: Hattie had joined the dogpile a few turns earlier and took 2/3 cities he had in the westernmost peninsula, so he was dead the turn after I gave him peace.

A nice side-effect was the diplo bonus I got from mutual military struggle from Hattie, which never worn off, IIRC.
After Gandhi was gone, MM and Hattie already had their rifles/gren running around, and RL clock was ticking fast, so I decided the fastest way to complete the game was to turn it into a "always peace" variant. I was also curious about the possibility of catching up in tech at this difficulty level. I had 2x land as my neighbours, would that help or hinder my progress?
Diplo was the obvious choice, as Hatty was #2 in pop and friendly with me - time to use the old UN giveaway trick.
Well, after a whole lot of infrastructure buildings, I reached Mass Media in 1595AD. Too bad I never got a GE, so I had to build UN the hard part - it took 11 turns for me to cash-buy it in Gao (1655AD). This was Mansa's city W of my capital which had culture flipped to me a while ago, and I think he rejoiced when I offered it back to him, and with a shining new skyscraper with a lot of flags in front of it - look closer and you can see it in the screenie.
End of story, diplo win in 1700AD for some 80k score, in my first victory at this difficulty level.
What I liked most, though, was to conclude that yes, if you attain a large enough land advantage, by knocking out a couple AI's, it is indeed possible to outtech the remaining AI even without ever attacking them - I never touched Hattie or MM. Of course, depends on map/civs/settings. I was skeptical about this possibility and was proven wrong. If I had the time, I'd try space race and I'm pretty sure I'd have launched ages before the AIs - I was already ahead in tech when I stopped researching for a while to cash-buy the UN.
Thanks to the admins for yet another fun game.
