can Lucee work with Cassandra DB easily ? I understand there's no Lucee extension, so querying Cassandra would require Jar with added driver to Lucee, and then calls to Java objects to be made from CFML

yep

We use cassandra since years ago like any other datasource with no problem: you need to install a couple of jars and then you can configure a datasource in lucee admin:

Thank you for sharing, interesting

We have one of our production servers talking to a cassandra DB. Really no different than any other DB.