I could go crazy with ideas, many of them probably out of scope of a "realistic" survival experience.
I'm a huge fan of moving villages/cities like the books/movie "Mortal Engines". So I'd personally disagree with your
But that's just me and I see why you want to limit it and on behalf of the realistic direction of VS, I do agree with you, personal preferences aside. Also, the larger the structure, the harder to make it running bug-free and performance-friendly I guess.
Small airships for exploring the beautiful landscapes would be awesome, and maybe in addition some kind of challange like weather. Yes, I'd like that!