I would like to suggest mirroring categories in other categories or listing types. This would be very useful to avoid creating multiple similar categories.
For example:
I have a category "Alarm systems".
I want this category under two other categories.
Motorcycle electronics -> Alarm systems
Motorcycle safety systems -> Alarm systems
It would be great if I didn't have to create two categories with the same names and different ID but could mirroring this one category under other categories or listing types.
Maybe this feature could be included in one of the next updates.