Currently SharePoint does not enable embedding from Promapp without generating the minimode link and including it in iframe code. We encourage users to share processes on SharePoint (e.g. accompanying a news item) and generating iframe code is a bit to advanced for many users. It would be helpful if the iframe code including the minimode link could be generated directly from the Promapp share menu.
Great idea, it would be useful to include any iframe options (height, width, other) in this option to make it easier to generate the code with a couple of clicks as opposed to typing it by hand.
If you do have a process for updating content on SharePoint as suggested in your post, a workaround for now could be to add an example iframe snippet so users can replace with their minimode link of choice.