I was in the same place as you a few years ago - I liked swarm, and was a bit intimidated by kubernetes - so I’d encourage you to take a stab at kubernetes. Everything you like about swam kubernetes does better, and tools like k3s make it super simple to get set up. There _is& a learning curve, but I’d say it’s worth it. Swarm is more or less a dead end tech at this point, and there are a lot more resources about kubernetes out there.
For anything that is related to my backup scheme, it’s printed out hard copy, put in an envelope in a fire safe in my house. I can tell you from experience there is nothing more stressful than “oh fuck I need my backups but the key to unlock the backups is in the backups fuck fuck fuck”.
And for future reference, anyone thinking about breaking into my house to get access to my backups just DM me, I’m sure we can come to an arrangement that’s less hassle for both of us