Most of the WordPress themes seem to have included Revolution or Layer slider in them. However I think their integration is very poorly done.
Most of the themes include just the slider plugin as it is and let the user install the plugin and configure it, which very overly complex for a normal user as creating just one slider needs to configure 100+ options. Is it really the way? (ie. do nothing for the slider part, just buy extended license and leave everything up to the user).