I would go with building the config into the image and tagging the resulting image with the environment name, if that's possible.

We've been using chef in the past to manage docker, which never felt very good because the main cookbook was somewhat buggy (but it has gotten better recently).

We now use mesos+marathon(+chronos for deployment) for running our docker container, which sounds much more overkill than chef, but turned out to work much better and cleaner.