He wouldn't have to go far: I think Rust's setting lends itself to castle builders, who have rolling planes and mountain peaks to take advantage of. That's what
Grayfade did: during a bout of illness, and with only Rust to keep him from turning into a grim, sweaty pile of meat and snot, he got all castley.
As is so often the case, boredom led to building which led to turrets: "I was sick over the past weekend so I had some time off of work, and subsequently a lot of time on my hands. I don't remember why I ended up choosing to play Rust, but I quickly got over the whole PvP and raiding thing and pretty much just built crap for a total of... like, four days. I spent 40+ hours hammering structures like a caveman. I started out just trying to make a little enclosed area and some stuff inside, but then I found this one hill. I walked up to this charming little mound, and as I was standing at the top looking over the nearby river and forest, I was just like, 'Yup.' So, here's the result of my boredom. The server I play on is probably getting wiped soon so this'll all be gone in a while. Here's what I made."
I love the 'lived in' feeling of Grayfade's creation. It looks communal and homely.
Xajar's castle build-- a 31 x 31 foundation castle that took down several forests in the making-- is a more formal creation. His 'epic build' feels like a show home for a potential client: it's clean and well made, though. And it's way better than the 1 by 1 shacks that typify my creations.
I think the choice of where you build has an effect: the beach here is flat and featureless; the grass poking up through the foundations of Grayfade's fever dream makes it a bit more appealing. He also mixed up a lot of building materials. Can you imagine what the two would be able to build
together? A big, big build, but crammed with detail?