Alicornutopia

It also previously appeared in the sandbox The endless waste.

I thought it might be Regrowth! So much fun.

Sable's sign suggests to me a gallery where people can put up samples of their worlds' deadly problems and what they know about solutions. This is what blight is like. This is what Phazon is like. This is what malaria is like. Here is how to try to find lakewalkers. Here is the model number of a good radiation scrubber you can buy from Bar. Here is a free sample of Bloom & Doom Pea Shooter seeds. Etc.

The pit is vast! \o/

*chants* "The pit is vast. The pit is perfectly square. The pit is bringing me immense joy."

Sunshine-style worlds would need a book to describe all the what their problems are. Or several. Some of which have already been written.

I’m not sure how useful such signs would be in general; even if we assume that everybody is perfectly helpful, I’d think that most people would only know how to deal with these threats if they had already dealt with them in their world. This could help some, but simply saying “late 20th-century Earth” or “Terraria” will give most of those people all the relevant information.

I suppose it could sometimes be helpful; one place might have a ward which only allows humans through, which can then be exported to Sunshine.

Regarding a sandbox with a solo Aaron: It's possible! Really, it's what he needs, but he's reluctant to go off and have adventures on his own because he would miss his brothers.

Revan has offered to take Aaron on FANTASTIC SPACE ADVENTURES, but we have yet to get that off the ground.

I welcome offers and suggestions for Aaron-template solo adventures. Besides Elarron and Orion, there's also the Attack on Titan AU version, who shares a name and substantial parts of a plot role with Eren Jaeger.

...Are his Miles and Mark analogous to Mikasa and Armin in some way?

Not exactly. More like they split canon Eren's plot role. I haven't actually decided what to do about Mikasa or Armin.