Kubernetes is great for single nodes! It definitely is more advanced than docker compose, but it’s actually not hard at all if you read through the documentation. It definitely makes running containers easier in the long run.
Here is my git repo for my big Kubernetes cluster at home: https://codeberg.org/jlh/h5b/src/branch/main/argo/custom_applications
It started out as just a NFS server and a Kubernetes server running on Proxmox in 2021.
I believe only the controller needs cooling, not the dies.