To piggy back on your “You don’t need k8s or high availability”,
If you want to optimize your setup in a way that’s actually beneficial on the small, self hosted scale, then what you should aim for is reproducibility. Docker compose, Ansible, NixOS, whatever your pleasure. The ability to quickly take your entire environment from one box and move it to another, either because you’re switching cloud providers or got a nicer hardware box from a garage sale.
When Linode was acquired by Akamai and subsequently renamed, I moved all my cloud containers to Vultr by rsyncing the folder structure to the new VM over SSH, then running the compose file on the new server. The entire migration short of changing DNS records took like 5 minutes of hands-on time.