Check out NixOS. It can build qcow images from scratch for you to import into proxmox
https://github.com/nix-community/nixos-generators
I have 8 bare-metal servers and I do everything automated with NixOS, I rarely ever access the servers directly.
Here are the nixos configs for my DHCP server and kubernetes servers that you can use as a base.
https://codeberg.org/jlh/h5b/src/branch/main/porygonz
https://codeberg.org/jlh/h5b/src/branch/main/nodes
For what it’s worth, Ive been using Ansible off and on at work for 8 years, and I think it’s pretty outdated and clunky these days, there are much smarter ways to manage workloads such as kubernetes, cloud-init, terraform, and NixOS. If you don’t want to get into Kubernetes then definitely learn NixOS.
Yeah Stalwart seems to have a lot of momentum, I’ll probably be setting up a server with my kubernetes+ceph cluster this month.