I won't go into my solution here, but the only tip I'll give you is don't use cloud based storage. Restoring is slow if we're talking terrabytes, it's expensive compared to buying a disk and your data is never truly safe.
Buy another drive, backup to it and have it on a rotation schedule. I keep my "offsite" backup in the boot of my car. If I'm not at home I'm usually away with my car.
Sure, but I just told you I'm running over 20 servers. Try running 20 raspberry pi's 😀
My resources are being shared for around 20W of power.
I gave up on using raspberry pi for running servers.
I ended up buying a $60 lenovo on ebay https://www.servethehome.com/lenovo-thinkcentre-m710q-tiny-guide-and-ce-review/2/ and then loaded it up with 32GB of ram. Now I run a proxmox hypervisor and around 20+ containers/VMs. Best decision I ever made. I just spin up servers willy nilly
If you don't need GPIO then run a hypervisor. Cheaper than SBCs and more useful.