I'm not an expert of LXC, but the DockerFile is really helpful to create everything you need without messing around with several configuration and files.
And think about the Docker HUB! It's amazing, don't reinvent the wheel!
I already have a domain registered on dreamhost and I didn't want to change nameservers. But reading about the alias concept and its cheapness, as you said, I think I'm going to migrate to R53!