An exemplary method includes a media service user interface system 1) providing a media service graphical user interface (“GUI”) for display, 2) detecting user input to launch a user interface customization mode, 3) launching the user interface customization mode, 4) receiving user input defining a customization of the GUI, 5) implementing the customization, and 6) exiting the user interface customization mode. In certain examples, the GUI may include a main menu bar that includes a set of menu objects representing a set of feature modules of the media service and a menu bar management object, the customization mode may be launched in response to a user selection of the menu bar management object included in the main menu bar, and the customization may be of the main menu bar. Corresponding methods and systems are also disclosed.