I’m not expert but for the sake of getting some discussion going:

Don’t open ports on your router to expose services to the open internet.

Use a vpn when torrenting and make sure your torrent client is set to only use the vpn’s network adapter. This way, if your vpn drops out the torrent client can’t reach the internet.

I keep everything local and use Tailscale to access things while I’m away from home.

I’m not a power user by any means but I moved over from obsidian and haven’t had any issues so far. I’m using the free cloud storage right now but will look into self hosting if I get more serious about it.