It could be a good thing if the GUI-toolkit used by the developers was shared with the user. Standardized GUIs are well conceived, nonetheless that doesn’t mean that they fit to the user needs and so on. Try every theme avialable on your desktop, let aside the look and feel, the structure doesn’t change but is more or less clear depending the theme.
So, having a lot of themes is great as well as to customize a toolbar, but that doesn’t touch really to the layout structure nor to its behaviours. That seems to be the same thing to have a lateral pane instead of a drawer, but not for the user because this is a subjective preference which corresponds to a reality at use. Last but not least, only the user knows what could be the best for him.
Of course, I let aside the kind of GUI-toolkit requiered for this purpose, obviously, it should be WYSIWYG, easy to use and so on; it could be a front-end able to struggle with GTK, Qt and Co°, or whatever. But, at least, there will be something in common between the developers and the users, that seems to be a win-win deal. Excepted for the consulting buisness in GUI design.
