Do you mind if I ask why you chose Docker Swarm? I don't know that much about Swarm and I'd love to know what you think about it compared to K8s (in terms of ease, nice things, things missing, etc.)
I'm a swarm user, but using single node swarms. It's the best solution I found for deploying apps. A lot of projects publish docker compose files, and those are easily usable with Swarm after some small modifications. I'm using the setup described at dockerswarm.rocks [1] and it's smooth sailing.
It's a real pitty, and still surprises me, Swarm is not more popular. It's still maintained [2] but few people still recommend it (even dockerswarm.rocks doesn't anymore). I've switched to it in 2022 [2] thinking I didn't take a lot of risk as starting with it is a really a low investment, and I'm still satisfied with it. I've deployed a new server with it recently.
1: https://dockerswarm.rocks/traefik/ 2: https://www.yvesdennels.com/posts/docker-swarm-in-2022/
I'm looking into K8s and other orchestrators like Nomad and perhaps will add support in Lunni at some point, but for now I believe Swarm is the sweet spot for smaller deployments (from single server up to maybe a couple hundred nodes).
Swarm still works pretty smoothly for me, although I'm worried about the Mirantis situation, too. I'm currently working on a new backend, which will also enable us to plug in other orchestrators if need arises.
Etcd requires 3 boxes for HA, but nothing stops you running a single node etcd.
I personally run single master clusters, because if the master goes down, you lose management as opposed to actual service availability, so mostly I don't care.
Now that there's anything wrong with your preference.