Try GunSmuggler [8192] - Northern Laxade Mountains
I'm testing all the known good seed of alpha 16.4b8. I'm in the search for large city like this one, in alpha17 experimental.
https://cdn.discordapp.com/attachments/501343472347906059/515188676150689809/cidoFX5.jpg
I found this one tooling around...
GunSmuggler [8192] -- creates a seed with 25 towns, 13 of which are large sprawling cities, all major POIs are there, some more than once (factories [shotgun Messiah/Shamway], Journey's End, The Ostrich, Construction Site, Red Mesa, etc.) and it has the Pharmaceuticals high-rise. There are at least 5 traders (but 3 are in a little centralized stretch within a few hundred meters of each other). The biomes are wonky and random, making the large city/suburbs appear partially destroyed as 2/3 of a city will be in a Forest, Snow, or Desert biome then the remainder will be Wasteland or Burnt Forest with ruined buildings, crappy land, and trash strewn about. I felt like it really added to the post-apocalypse feel of the game's immersion. The land in general is mountainous with town valleys between. Water is pretty scarce and spread out, with little ponds here and there, and only a couple larger lakes. There are no large rivers running through the map. Also, the roads actually make sense and the highways connect one developed area to the next.
Note: Gunsmuggler [8192] (Juyipa Mountains) is a similar road map layout with shuffled topography, POIs, water bodies, and biome locations.
These may not be a singular large city -- but they are like a huge super city with suburbs that extends across the entire map due to there being only 30 seconds to 2 minutes travel (roughly 2-4 city blocks distance) between the large town/city locations. There is literally endless buildings to explore!
:rapture: Hopefully this helps you out a little!