k8s won, it's kind of madness not to get onboard at this point. Yes, sure, you can do the 'same things' (almost) with nomad apparently less complexity, but k8s isn't anywhere as hard as it was a year or two ago today..
Nomad is the BetaMax of container orchestration. Better quality than K8s in a lot of ways (supposedly), but there's no ecosystem around it so it's a moot point. Want a continuous delivery system that plugs into Nomad a la ArgoCD or Spinnaker? Or a serverless platform that can run on top of it. Or access to people that know how to use it. Be prepared to write your own Nomad bindings and train your team on it.