Change Chef for Ansible and I have the same architecture. And you know what? I have decided to put on hold K8S until persistence is properly managed.
Meanwhile, we have decided to give a chance to serverless architectures with AWS lambda.
I agree that persistence in k8s is tricky, especially at scale, but at least in our case that doesn't drive us way from the platform. Kube is awesome for services, and if we have to keep a few things on gcloud instances bolted to reliable storage for the moment that's at least less heterogeneous than what we had before kube came along. In other words I don't think you have to kube all the things to see a lot of benefit.