Well probably yes, technically this is possible. But the image will be out of date as soon as it is online I guess
What also speaks against an image is that you do not learn about how pimatic is structured and where the data is on the file system, how to deal with the config.json and so on.
From my point of view I wouldn’t have learned so much about Linux if I would have used a ready made image.
We have discussed that a view times before and there have been other users requesting this.
Sure this is the easiest way, at least for a raspberry pi. I will try to update and enhance the pimatic installer the next days so this will be an alternative to the ready made image.