ubuntustudio-desktop are called meta packages, packages without any real content, but that pull in a bunch of other packages as dependencies. This makes them rather tricky to remove without the logs.
I've looked through the stuff
ubuntustudio-desktop pulls in and figure you should be able to safely remove the following packages:
sudo apt-get remove ubuntustudio-desktop xfce4-cpugraph-plugin xfce4-dict xfce4-fsguard-plugin xfce4-indicator-plugin xfce4-mailwatch-plugin xfce4-mixer xfce4-mount-plugin xfce4-netload-plugin xfce4-notes-plugin xfce4-places-plugin xfce4-power-manager xfce4-quicklauncher-plugin xfce4-screenshooter xfce4-smartbookmark-plugin xfce4-systemload-plugin xfce4-taskmanager xfce4-terminal xfce4-verve-plugin xfce4-volumed xfce4-weather-plugin xscreensaver xscreensaver-data xscreensaver-gl xubuntu-icon-theme ubuntustudio-default-settings ubuntustudio-icon-theme ubuntustudio-lightdm-theme ubuntustudio-look ubuntustudio-sounds ubuntustudio-wallpapers xfce4-appfinder xfce4-notifyd xfce4-panel xfce4-session xfce4-settings xfdesktop4 xfwm4 plymouth-theme-ubuntustudio
That should clean out almost everything you don't want.
Take a quick look through, just to make sure you don't recognize anything you want to keep. From what you've said in your question I don't think there will be anything.