As a former product owner I initiated family retrospectives after smaller or larger events like holidays, stadium visits, changing family bank accounts, moving, etc.
We discus what we found went really good or bad and what we need to look out for next time and note everything.
This might be a stupid question, but here goes anyway. Why not install Ubuntu server without proxmox and run docker and Portainer the way you described it?
First right, then left. Very gentle, as overpressure is bad.