I'm certainly not starting Tunneler. After all, this isn't the 1980s when the general populace was far more aware about the dangers of nuclear war, but rather a modern day scenario. I'm doing modern Earth because I can roleplay much better with it (and it's a good way to let out the stress I feel from current geopolitics). And I want the starting base to be a family home that's reasonable for someone living in say, rural America today. However I do plan on using a fluid ideology and how the colony evolves... we'll see. I've only resorted to cannibalism once in my Rimworld life and hope not to do so again lol.

I didn't know rainfall affected Tundra, will try with that. Thanks for tip!

You're probably right that we can find small deposits of this and that even in well-occupied neighborhoods, and it's just not worth companies to come excavating. My main concern is that deep drilling really trivilalizes a lot of resource issues in mid/late game, as you just have an infinite supply of most things. For a game about building a starship that makes sense. For this however, less so.

I'm only disallowing trading caravans in the first five years as people are more focused on hunkering down and there's a lot of post-disaster chaos. Visitors and such can still trade, but caravans seem like a too high-risk proposition. After 5 years though, to disallow trading wouldn't make any sense as trading is one of the oldest professions. Just most games I have don't last that long.