I also posted this on r/AskPhotography, but I figured I'd ask here too.
I recently got a new phone that, among the other features that made me want it, came with a pretty neat camera setup. The features of the camera helped me realize that doing more than basic pictures is actually pretty easy (I know, doing really good stuff will take a lot of time and practice), but I find that it leaves a bit to be desired when shooting at night (even when editing RAWs - though I also need a lot more practice with that), and I could do with a longer lens. Also, while it does have multiple lenses and pretty nice zoom, the aperture is fixed for each lens. It's a Sony Xperia 1 III, since I just noticed I hadn't mentioned that.
When I was younger my parents had a Canon EOS Rebel of some variety (I want to say a 70D?) that gave pretty good results for taking pictures of nature and birds. I also have a Panasonic point-and-shoot that's pretty okay but loses a lot of flexibility when you take it out of the "Auto" mode, it's old enough that to my eye my smartphone camera matches it in everything except optical zoom. I now live in Japan and I like to travel and take pictures of the landscapes and cities, and also buildings (in particular, temples, shrines, and castles), and sometimes close-ups of assorted stationary objects. I'm also interested in being able to take night photos of cities (so like, dark with bright points of light from things like neon signs or lanterns) and sunsets and such. I very rarely take pictures of people, and I have very little interest in video functionality.
I'd like to spend under ~$1000 USD since I'm not planning on doing anything crazy, I just want something that'll do well in low-light situations and will have a decent variety of extra lenses and accessories should I want something in the future. Mirrorless seems to be the way to go for what I want, but it also seems like the options are a bit more limited within my budget range.
The three main options I'm considering right now:
Used Nikon D3500 w/ 2 lens kit - ~$550 - the lowest general quality/performance, but seems like an overall very good deal
Used Fujifilm X-T2 w/ used 18-55mm lens - ~800-$900 - good price/performance balance, but only has one lens
New Fujifilm X-S10 w/ 2 lens kit - ~$1300 - a bit over-budget but has a LOT of nice-to-haves like IBIS, Bluetooth, and a built-in flash. Also it's new so fewer risks
Thanks for any advice you can offer!