I haven't used Docker Swarm (I have barely used Docker Compose), but I have run a couple on-prem Kubernetes clusters (at my house and for clients at my day job) and cloud Kubernetes clusters, so I can speak to how complex it is it set up and run.

My background is systems administration, engineering, IT, and now DevOps. I've been using Linux since Ubuntu 6.06.

I set up my Kubernetes cluster with kubeadm because I wanted to learn, and it took me about a weekend to get my single master, two worker cluster up and running. I think you could probably do this using k3s much faster and have less learning curve (you don't have to care as much about Container Network Interfaces, for example, because k3s makes that decision for you.)

There is a lot of documentation out there on Kubernetes. Helm as a "package manager" (really a templating engine) can be nice if the software you want to deploy has a Helm chart that is well written. Writing your own Helm charts can be a learning process, I've modified some but not written one from scratch yet.

Kubernetes releases new versions about quarterly. I've done several upgrades on my primary home cluster over the course of the past 2 years and they've been pretty smooth, about an hour of time investment ~~total~~ each. And remember, I'm on the more nerdy and complex flavor of Kubernetes. I think with k3s these would be even smoother and quicker.

I feel like Kubernetes knowledge is probably more valuable out in the industry if that's a factor for you. I haven't come across any Docker Swarm clusters in my DevOps travels, just Kubernetes and some HashiCorp Nomad.

I'm curious to see what folks say about Docker Swarm. If you have any questions about Kubernetes or running your workload on it, I'd be happy to try to help!