Sorry for not getting back to you sooner! When we first implemented the menu, we quickly investigated supporting sub-menus. The main difficulty we ran into was doing it well *and* working across various templates. The last part is the most difficult as CSS is easy to conflict with.
With that said, your example code definitely helps with some ideas. I've added this item to our to-do list to investigate in the future. I can't give any specifics on when, or if, it may be implemented though.
Thanks,
Alex
show user menu > dropdown-submenu
