A profiler hook was implemented in 2.5.3 that allows you to monitor requests. Although this system was setup for profiling for performance, you could also use it to distill some info on what types of data people are reading or writing.
There are four hooks at the moment, two for enter/exit runtime (which also provides the JSON request, ie xpath etc) and two for enter/exit database (which record the actual sql commands)
To use the profiling mechanism, you need to implement a class that implements the com.mendix.systemwideinterfaces.core.IProfiler interface, and then register it via
Custom Edit button that writes an audit record as it opens a row?