Would make a lot of sense to integrate it, as noted in my blog post.
I would stay with the default port and if building with the +nomad option, I would also add the port to the exported ports automatically for the image.
Currently changing the port would be creating a YML file and writing it.
This might still change in future. So I am not planning to add support to managing the YML file in a beta.
But copying could be another option. Or mounting it ...