Opensstack with Rancher ( rancheros ? ) - conceptual question

I am already running rancheros/debian hosts with rancher on baremetals/proxmox/aws/gce and now it thought its time to think if we migrate one of our proxmox servers to a openstack appliance.

The point is, we run more and more in docker, actually any infrastructural service which is touched or update, is moved into a docker container stack (production).

We already run own rancher-catalogs, private and public and all that - so we are kinda deep dived into the rancher-ecosystem.

Using a cloud-image based appliance seems to be next logical step, since docker-containers are no first class citizens in proxmox, but we rather run them through and rancheros VM.

Seen in the forum, that people got their openstack to work, i see that its mainly happening through rancheros, so the containers are started in a provision KVM vm, right? So basically rancher+openstack means, that rancher starts a rancheros kvm (using cloud init ) on an openstack using the machine-drives, instead of me provisioning a rancher-os server on proxmox myself, running an rancher host and being at the same spot.

Anybody has a second to explain his idea/conception main differences between those bold worlds?