Admin Backend Metrics

Im interested in hearing any advice/tips on what or how to build an
effective administrative backend for monitoring user input and actions
while on my site. Some of the metrics that I’ve read or heard about
that can be useful are:

-all user inputs for any field
-tracking user movement and actions from page to page(i’d love to hear
implementation ideas for this) -a place to disable/enable users

Is there anything else you can think of?