So I had a city block design before the space age update that I was using, but now all the rails are invalid so I am back to the designing board. I like making my own things but I've definitely learned to appreciate insights others with more experience may have. So Perhaps I should start by laying out some of my design goals:
- The edge of a city block is the exact distance between radars to reveal adjacent non-overlapping chunks.
- The city block (if possible, the new rails may not allow this) should have rotational symmetry in the corners and edges (which I think makes the whole thing rotationally symmetrical) and snap to an absolute grid (making it easily tileable)
- The city block carries power and logistics network along every edge (the area inside the city block should be left empty to allow for isolated logistics networks)
- Trains should be able to travel along every edge in either direction, allowing for left and right turns or straight through. U-turns are not necessary but could be fun to try and add in
- Train intersections should allow maximum thruput (ie 2 left turners approaching from opposite sides should not block each other)
- Train intersections should prevent deadlock (I have observed deadlock occurring in this type of design where for example 2 2-8 trains fit along an edge, after the 8th train enters the inner loop of one of these city blocks it prevents right turners from entering that space and thus causes deadlock. I prevented this using circuitry to not allow an 8th train to enter a city blocks inner ring)
- City block should have some design (separate blueprint) for trains to take an exit offramp, wait in a queue to arrive at a stop inside the city block where they can unload into chests that are outside of the external logistics network (the closer this is to the border of the logistics network to allow for the most internal design space the better). If possible, allow for 2 train stops per edge (my old design allowed for this)
- carry along the power lines a shared (global) circuit network (red and green) and an isolated (local) circuit network for the internal city block (the internal one mostly so it can be easy to observe the state of a city block from the map by hovering over a power pole)
- Be as pretty as possible

Current design (Intend to replace as it is fleshed out): https://factoriobin.com/post/qxkrpr
I welcome any more potential design constraints you might suggest adding that could improve the design