The Sims castaway!

They don't seem to be doing stand-alones any more. Maybe they can have a castaway island vacation world where your sim has to complete a castaway aspiration in order to escape back to the residential part of the game? Or maybe they can have an expansion pack where you have a choice of survival adventure destinations, each with it's own aspiration?

I honestly have been making my own types of natural survival and magical survival challenges. And it has been fun.

Basically, making heavy use of the Natural Living Skill from Enchanted by Nature (or if an occult heavily relying on their magical abilities more).

One (non-occult) Sim I treat as homeless, floating household to household, or living in a trailer or wreckage. The amount of raw fish and frogs that I make him eat—is almost criminal LOL.

At this point unless they make an apocalyptic survival skill and pack. To make more urban scavenging (at this time I do use Freegan trait with the NLS though), and alternate challenges and threats—I feel much of survival (self-sufficient) type gameplay is already available in Sims 4 with the right packs.

I've done this for years with Island Living but as HollownessDevour​ mentioned, the Natural Living skill adds another dimension to it since it's been added. I make my Sims survive with nothing on a deserted island and eventually they not only survive but they prosper sufficiently to build themselves a house elsewhere. 

I've mentioned this before when players have talked about this theme, but the last Sim that I played as a castaway was also a crafter, Freegan and forager and while surviving on an island she made her own home. Everything was foraged or hand made. The only thing I had to buy was kitchen units because she was dumpster diving with Eco Lifestyle and couldn't find matching units. I made her house out of wood and glass walls so she didn't even have to buy windows. I set up a public workshop so she could eventually travel there to paint, knit, make flower arrangements and pottery, etc. But what I liked about Castaway was that the Sim had to actually collect the materials to build the house structure and I'd like to see that in the game again.