That's what we basically trying to do in the future, however that's really hard to do if you want to have a running etcd cluster with 5 nodes all the time. You would need to check if one etcd died, and then either promote a proxy to a etcd master or run a new machine (the later is only possible in clouds or virtual environments)
You can do that trivially with Mesos and have it always ensure 5 instances are running. Bonus points that it will run identically on bare metal and cross cloud which means less vendor lock in for you.
