I am playing skyblock on a server that limits the villager count to 10. I know I can make a typical iron farm with a 2x ring of farmland that some of the villagers work and a rail system under it can collect the drops. I can probably even setup cative trading booths for the villagers of the other kinds.
As long as there are villagers close enough to detect all the doors of the iron farm and enough villagers in total within the "village" there shouldn't be any need to keep things symmetrical.
So you could have trading booths on one side of the iron farm and farms on the other, or if the iron farm is small enough you could even have all the villagers on one side, though that might be limiting.
After studying the rules that apply to villagers, doors and iron farms I still am not 100% certain but I think the following should work:
- Use the standard 2-tier 16x16 golem spawn pads.
- Place only 8 valid doors next to the spawn pad, each touching the center of a side. The doors would be at the same y level as they get placed in a traditional iron farm.
- Place another 8 doors just under 32 blocks outward from the previous doors. Remember that a valid door needs access to skylight on one side and "sort of a roof" on the other (full details are explained in many tutorials).
- Repeat as many times as desired until you are far enough to put all of your farms in the desired space.
- Place any additional doors symmetrically so that you have at least 32 (4x8 per side). The extra doors can be right next to the pad if you don't need the space. You can also make your single village bigger by using more doors in the same manner.
- Place your villagers all at the same y level as the doors, so that at least one will always be less than 16 blocks from a door.
This is why I think it would work:
It does not matter where the villagers are, since they are all within range to detect at least one door.
- Whichever villager the game picks to start checking for a village will detect a door because it is less than 16 blocks away and from a village.
- Then it will detect the other doors in sequence, adding them to the village until they are all included. Since the doors are placed in a symmetrical pattern around the spawn pad center that will become the village center, causing the golems to spawn there.
- And in the meantime... All of the villagers are either doing productive work or being held captive in convenient booths for trades.
And of course, make sure to place no other wooden doors any closer than 32 blocks outwards from the village center. And don't forget that it is a sphere, not just a circle.