It would be really usefull to have an option to "show only not installed"/"hide all installed" packages. This helps when you have a lot of new/uninstalled packages and want to test them one by one, so you don't have to scroll through all packages, including the ones already installed. With that you can use var_browser for all new vars and for example BrowserAssist from JayJayWon for all known vars, with tagging and so on.
I cost very much time to modify the mechanism.