CoreOS actually makes this significantly better with their Cloud Config capabilities. With CoreOS and Docker, we've successfully deployed this at a number of companies.
With that said, there has been plenty of support to be handled, and we need to get better at doing multi-node deploys, but we're learning. :)
Well, you're quite lucky to be allowed to use CoreOS. In our case, only a minority of customers didn't want to dictate the distro to be used.
In one extreme case, we had to install on SLES 10 (in 2014), without root or sudo, and then hand over the machines, since we weren't allowed direct access to the production system. And maintenance involved sitting with one of their sysadmins and telling him what to do :)
With that said, there has been plenty of support to be handled, and we need to get better at doing multi-node deploys, but we're learning. :)