Simplify Panels "Add content to" popup with fewer options for end users Echoing this unanswered question on D.O.

Is there a way to limit (and possibly reorganize) the Panels content types and panes presented to website editors?

Basically taking it from this:


To this:


I tried using some of the cTools API alter hooks, but no dice.  Any pointers?
Checkout https://drupal.org/project/Panopoly - they make a lot of customizations to this to improve the ui.

Some more details from the project page:


  Panopoly is powerful base distribution of Drupal powered by lots of Chaos Tools and Panels magic. The distribution is designed to be both a general foundation for site building and a base framework upon which to build other Drupal distributions