I wonder (pun intended), and time willing may give it a shot, how successful someone like Germany might be at this challenge - would take a little setting up at the beginning and would probably miss some of the early wonders, but get a hansa surrounded by commercial hubs, stick in Magnus with Vertical Integration, and just go HAM on Medieval/Renaissance wonders (plus you're probably getting all the Great Engineers - Imhotep seems like virtually a necessity for this challenge).
As it turns out--rather well!
Deity/Germany/T160/20
At this point, I did not have space for further wonders; however, I realized belatedly I could possibly have added Sydney Opera House and Venetian Arsenal with better planning and culture. I also did not employ the full HoF min-maxing and could probably have shaved turns off with a few jungle chops and cheaper wonders.
These are pretty standard settings for me these days, but I copied Bangau's AI and curated the city-states and wonders.
So let's get into it: yes, I did finally roll an Ik-Kil start and it was as much fun as it looked
Basically, from a few attempts to crack 17, I have developed a quick slingshot strategy for Germany: prioritize Apadana plus two early wonders, beeline apprenticeship/feudalism, settle with Ancestral Hall until printing researched, beeline industrialization and prioritize guilds/exploration/mass media. The many downsides include having 3 cities at T70 and offering little to no assistance to the satellites. But around T113 every city starts completing hansas and commercial hubs and production can quadruple in the capital with vertical integration and trade routes.
In this case, I actually missed Ik-Kil on T1 and had to backtrack to settle on T4! That said, the deep cenote waters aided a 17-turn Etemenanki that led into a Lady of the Reeds and Marshes pantheon. After Apadana and Temple of Artemis, I settled ~10 cities. Ik-Kil was most impactful for those wonders plus Forbidden City, which, no matter what I seem to do, always demands more production than I have on hand. Etemenanki was very lucky as I have never snagged it on Deity, and the Oracle was also a steal. Gossip revealed Sweden had started it ~T90, so I plopped it down and Isidore completed it.
I find the mid-to-late-game to be the hardest, because, while production ramps up, there are many highly positional wonders that just fill in the blanks. When Oracle goes, there is not always a way to use all the hills. It's very easy to lose out on any number of wonders at this stage. Other tiles, like the deer on the far side of Ik-Kil just seem impossible to build on. Once Cristo Redentor was complete, it was just a matter of filling in all the excess river tiles.
Now, I don't think Ik-Kil is essential, but I will definitely say the amazing starts where you are spoiled for choice in positioning and production help a ton. Thanks again for the fun challenge!