As far as what is possible with v10.6 ... with a little investigation you may be able to extract and report on the CQL/select statement behind the query. Based on some googling, typical usage of the SelectStatement involves creating it using QueryProcessor.parseStatement() helper method, like so:
selectUserStatement = (SelectStatement) QueryProcessor.parseStatement(query).prepare().statement;
So what you can do is setup AppInternals to collector the first parameter of the method QueryProcessor.parseStatement -- that should contain the query string. To do so modify the configuration assigned to the JVM querying Cassandra and the following monitoring filter:
Save the filter setting AND remember to scroll all the way to the end of the configuration screen and save the entire configuration -- this is a gotcha as you may not realize there is a save button at the bottom of the screen.
Restart the JVM for the change to take effect. Then exercise the app so that queries are executed. You should then be able to run the following search:
parameter = 'cqlquery=*'
That should return the list of CQL queries [... presuming QueryProcessor.parseStatement was used to create the SelectStatement or CQLStatement].
If that works, you further report on transaction times by cqlQuery using the following:
parameter = 'cqlquery=*' | timeseries -group_by parameter = cqlquery
The main assumption here is that QueryProcessor.parseStatement() was used to create Statement object. If this is not the case and you have access to source code, you can inspect it and figure the apt method and parameter to capture.
If that seems a little daunting, I suggest reaching to your friendly neighborhood Riverbed APM Solutions Architect and they can help you. If you do not know who that is, we can follow up offline.