The solutions you've mentioned aren't exactly equivalent. Proxmox is a hypervisor while Docker Swarm and Kubernetes are container orchestration engines. For example, I use Proxmox in a highly available cluster running on three physical nodes. Then I have various VMs and LXC containers running on those nodes. Some of those VMs are Kubernetes nodes running many Docker containers.

I highly recommend Proxmox as it makes it trivial to spin up new containers and VMs when you want to test something out. You can create and destroy VMs in an instant without messing with any of your actual hardware. That's the power of a good hypervisor.

For orchestration, I would actually recommend you just stick with Docker Compose if you want something very simple to manage. Resiliency or high-availability usually brings with it a lot of overhead (both in system resources as well as maintenance costs) which may not be worth it to you. If you want something simple, Proxmox can run VMs in a highly-available mode so you could have three Proxmox nodes and set any VMs you deem essential to be highly-available within the cluster.

For my set up, I have certain services that are duplicated between multiple Proxmox nodes and then I use failover mechanisms like floating IP addresses to automatically switch things over when a node goes down. I also run most things in Kubernetes which is deployed in a highly-available manner across multiple Proxmox nodes so that I can lose a physical node and still keep (most) of my services running. This however is overkill for most things and I really only do it because I use my homelab to learn and practice different techniques.