Is there any away to randomize a display message in rules?
The display message can be customized by following this procedure. You might also want to write a custom module, which may enable you to control your message display by user role.

If you want to display the status message in a different way, (there is a module for that ;-) too) try Better Messages module.  


  Better Messages is a very simple module that provides "Popup-like" Drupal messages.