Going to answer that myself:
It could be possible, to use the Postman API, to send a request to the collection and then do some JS filter magic. Sounds like a bad idea overall.
What I ended up with is JSON Schema Validation. This appears to be the cleanest solution. The saved responses/Examples help to create JSON Schema with this tool https://www.jsonschema.net/, then adjust the schema an then use AJV as described here: Checking a schema with tv4 - #2 by dannydainton
JSON Schema makes a lot of sense and adds value to the API development. But it’s also a buttload of work.