I took a look at the coreos fedora project[0] as listed by you and others, but it looks immensely experimental right now. From the FAQ[1]:
> Fedora CoreOS is under active development and there are currently no downloads available. However, you will be able to download the images from one canonical location via the CoreOS and Fedora websites. The discussions around this development will happen on our community channels.
I actually really like Ansible -- it plays well with other tools, scales from small to large infrastructure management needs, and has great documentation with enough escape hatches to make hacky (but functional) solutions possible. I have less of a problem with ansible and more being forced to move more and more into tools that push me towards OpenShift when it doesn't make sense for me.
[0]: https://coreos.fedoraproject.org
[1]: https://coreos.fedoraproject.org/faq