I’ve only just found this thread, so I help it’s not too late. I’ve found myself banging my head against a keyboard on multiple occasions when I’ve forgotten to change database before executing an insert, only to realise an hour later why my change isn’t working as expected.
We have existing processes to manage our indexes/overall schema, so adding an option require_existing_collection to thousands of operations in code could take a significant amount of effort and not address the mode by which most mistakes happen; making manual changes on the command-line.
Could the proposed createCollection workflow could be made a config-level behaviour? From my perspective, the “challenges” you list above are all good things for deployments with well established collection formats and management mechanisms.