Funny you should bring up these as examples. I've made (1) and (3) using an existing object mapper. They were made out of limitations with JPA/Hibernate and for higher-level functionality in logging. The ORM was never sent to prod. The logging events were gold. Specific events were 'major' and filtering on a user ID in a narrow timespan could show the expected/unexpected events for the traces as a sequence diagram through all the microservice layers. Clicking on an event then searched Loggly for all logs for trace-id at time. It got to the point that non-techs were answering customer issues with it and we hardly had to check/wait for Loggly to answer.