Hello, I have not played with your mod, but will include in the next run.

First I have not played yet with your mod, only made a detour to van Neuman, so there are my thoughts / findings, but from the look at the recipes and my own feeling about SF and all
So probably some ideas are included but I have failed to see them.
Also some could be not really totally thought through

Generally I see this sort of remains of a long dead civilization with probably got extinct due to technical failure / van Neuman system gone bad)

There are some thought of me for such a high tech mod/civilization mod

• I think the link of this (set of planet) should be only through Neuman and fulgora, as a far Trojan; but I think linking it to Aquilo could also a thing as being very cold and more like advanced game (so I think remove/optional especially other routes if using nexus-mod)

• The other three should be also a long distance from neuman or anything else, I think opposite of the sun would be fitting, or some like farther out as aquilo or solarsystem-border; at least it should be realtively hidden

• I would see the distance from nauvis planet to vanNauman around 10.000km, then the other 3 sort of 25.000km from vanNeuman

• As being a very old death civilization the planets (aside from Neuman) could be circling an own center (like artificial blackhole or white dwarf) like sort of Jupiter or probably also a entirely other solarsystem (like nexus-mod)

• If doing a separate own system with this mod, one could place a (small)(failed) van-Neuman in nauvis, where one can research the location of the new system

The Circa ringworld is not resaonable because a technical band around the should be noticeable from nauvis

• You can label it as brocken remains which would explain that its not really noticeable

• have some cracks, gaps in the ringworld, so you can have/need some ringwold-landfill (using the space-platform- with some reinforcements (ceramic or some special form this mod. Like nanites for infrastructure )for this planet

• Gold ore / bones seems not fitting the theme I feel, because both are sort of dependant of some former living / new planet in development, but a ring world is definitely build so I think these both will not really be available in this manner, as it would make more sense to store the readily useable resouces, like metal and the powdered bone-material

• Change gold to ceramic
• Gold is sort of common material, so probably avoid intersections with other mods (lignumis for example, which I sort of also want to include in my next run)
• Ceramic is artificial and fitting the high-tech theme, one could see that some warehouses exploded thouse some mineable areas ( so far all gold items could just be renamed, as ceramic can be a optic- or superconductor-cable, also ceramic-insulation exists)
• Ceramic could be used to have improved heat related items (thruster, furnace,….)
• If using Ceramic, the bone fragments could be ceramic powder or calcite
• Also for the ceramic viewpoint you can rename the Silica sand to ceramic powder
• If you want to have some recipes with this ceramic you can add probably a recipe for vulcanus to get ceramic from calcite /stone / lava

Van Neumann / Nanites from the detour to van Neuman, so there are my thoughts / findings with my quick stay here

• I see that it as an area with a bunch (squares) of vanNeuman probes running out of resources and come to a halt or by some error

• The gaps could be more wider, but that’s just a feeling, probably twist them around?

• The gray goo should be way less available, probably only a starter amount, them more like oil on nauvis (but i think its on purpose to have them plentifull, so not all my thoguths/ideas are really fitting your setting)?

• If you see the Platforms there as specific out of nanites and have it as landfill-type (there is the recipe of platform-tiles from nanites) and make the areas with the Landfill-type, you can remove and the tiles and rework them into nanites, so the Location is selfeating,. so one need to be carefuil here

• Add a recipe of fresh nanites from iron/copper/plastiv-plates from Nix, here you could even try to include some other items from your set of planets to make all this more needed

• So this way you need to work a little more effort for getting the nanintes, but more paths are open ( from grey-goo,from platform-tiles, and even some more from fresh resources if you add a recipe )

• Without Rocketsilo and CargoPad it’s a very limited place

• I was not able to find/use the rocket-part recipe from nanites, but I find it ok to import all the items for rocketsilo and rocketparts, because in the vanNeuman-loacation there would be no organics, so no fuel, so it has to be imported (I have researched all with a console command, so probably I have avoided some scriptings?)

• Blue card and LDS from nanites are ok, sould be a little cheaper as their normal conterparts if constructed from raw resources and only useable in zeroG

• For the Science it would be reasonable to add (later research) some of the usual Science-Packs (Automation / Logistic, Production (seems reasonable to get the knowledge of the nanites; maybe also Utility a/o Electromagenitc)), at least with NIX there seems to be a location in relatively near source, this would be fine if added with option

• Do some additional improved moduls with nanites (quality because nanites could be better, finer manufacuturer; productivity, because they save more on the material used)

• A little challenge could be added if it would be possible to have the nanites occasionally break-out (spoiltime?) then could be handled (terminated) with the teslagun, if not they could be eating away your factory  so handle with care

• Use nanites to improve some more other items (recycler….)

• Nanites-Repairpack

• Add some advanced breakdown recipes (recycling, crushing, tar processing) with use of a portion of nanites (ie. Ice chunk using naintes an getting back 90% nanites with an improved output, should also take a lot o energy because of naintes)

• I like to think of having some 5th quality builds directly from common ingedients plus a heap of the advanced items from this mod only possible on vonNeuman location

• Propbably use as ingredients for Ringworld-tiles (above mentioned)

• Naintes Gun ammo / missles (with the idea that nanites can disammble things faster as just hitting them with some mass) (Nanites ammo could be having some spoiltime, with spoilresult for the simple ones (problably inert missles?) so adding a little complication to have them produced fresh for the advantage)

• As a side idea : use nanites to build parts of the Rocketsilo, (ie. 4 parts…) which then can be lifted inside a rocket (weight 1to) so one can send a rocket silo almost complete instead of all the single ingredients

• I think some ZeroG buildings should be doable out of nanites to have a good remoteable working location, all can be way smaller and with less performance, due to a probe being a smaller location as a planet, so not needed the full planet performance in this small enclosed space, plus recycling/back-build recipe with say a 10% loss of nanites ?

• (RocketSilo & Cargo Pad, Radar, Logistic (Roboport, chest, Bots)) Steel-chest, Fast inserter, Pipes…)

How about some Antimatter asteroids in the near vicinity and orbit of mirandus (and probably shattered planet), there need to be a reasond why both are shattered ;-)

• Antimatter grabbing seems perilous, so probably restrict to a specialized grabber ?

• Antimatter fuel could be finely tuned high tech fuel using antimatter plus some precessed ice and iron (asteroids) with some supercondutors and accumulators to keep the antimatter contained

• Antimatter items could be having a spoiltime with an explosive result (and a recipe for refresh /and neutering antimatter items)

• As antimatter is very delicate to work with, a heap of nanites(which will be used up whole) for the antimatter recipes

• Antimatter –rocket for use on (I think some like energy jumps as with tesla could be nice and fitting for more mayhem for big (and bigger) demolishers but need to be very dangerous for oneself

Asteroids

• Some other antimatter source could be planets with a high magnetic field
  https://de.wikipedia.org/wiki/Alpha-Magnet-Spektrometer
  https://en.wikipedia.org/wiki/PAMELA_detector

• Of course this should be only available after extensive research

• Metal – Convertion recipe feels sort of to simple , maybe add some side-ores with some pobablity like asteroid crushing.. ..

As spoiltime is sometimes not very well received as mechanic, but probably as option, but I think its fitting for antimatter and the nanites(they are very heavily worked on, so some replacement is reasonable)

Mirandus-science could reaveal the reason why there is a shattered planet and its position

If van Neumann and Circa are space borne (platforms) both could be having some sort of asteroid problem where one need to protect against like with a spaceship, could be also special asteroids (parts from derelict tech from some failure)

As I see you mostly rely on your own science pack only to advance your reasarch, but with Nix available it would be reasonable to include some base science pack (maybe an option?)

In my mind vonNeumann is a selfereplicating probe for search and build liveable planets in the universe, so the vNeuman-Science could be used as prerequisite for locations beyond aquilo, because we need to filter out the loacations from the vNeuman-science

That was obviously to much for this comments page...
Sorry for the wall of text; i try to explain my ideas

I hope you find this interesting and help you
I am very excited to use your mod and see where its heading