Everything you need is there. Floating IP's to do HA at the front. Use something like HA proxy and monitor whatever it is you need such as response time from the backends. Once that passes a limit call a script to poke the API and provision you a new node. You could use something like Ansible to provision the node and then place it in to load balance.
Thanks Mark. I was thinking that because I would like the whole point to be that you can deploy it anywhere and if you would like to enable the federation (when we get round to writing it). Is their a license you would suggest?