I will suggest that you make it more intuitive to browse folders including subfolders by adding a subfolder on/off switch (see red text).
Thanks for your suggestion. We're always looking at ways we can make the interface more intuitive. I'd be interested in hearing from anyone else as to whether or not this would be useful for you. Please leave a comment or vote for this request if it is something you would use.
Turning sub-directories on and off is important to me; I frequently work on projects with more than one shooting session. I find myself starting up Adobe Bridge to deal with that -- which never ends well since Bridge is big, slow, and flakey. But I never remember how to do it in Photo mechanic.
This feature would be awesome - it's called Drilldown in Kyno, and that's a good example of how it can work.