I backed up my configs, made snapshots, and rebuilt each VM from scratch. If I forgot to copy a cron script, i pulled it from the snapshot. It took a full Saturday, but it was a chance to apply everything ive learned the last 3 years and improve some architecture decisions I'd made when i was first learning. With proxmox, you can build a VM that has the basic things you'll change on every machine (networking, docker, automatic updates, ssh keys, monitoring) and clone it for each server you need.