1. The possibility to select per project in project properties if it is a PHP4 or PHP5 project. See also changing-version-of-php-in-phped-t2954.html
2. In Code Explorer two buttons or keys to open or close the function trees. When close you see only the functions. Easy when you have a class with a lot of functions.

If you have a class with a lot of functions, you may prototype it in a php file and include that file in the "Code Insight Includes" list, like suggested there http://forum.nusphere.com/code-completion-for-php-spl-dom-pdo-and-dom-t1733.html