The use case is User wants to change his password, by accessing the Server Manager.
If no URL path is provided, Nethgui redirects to Dashboard. This is quite hardcoded. Then Dashboard decides what to do. If User is an admin the Dashoboard is shown, otherwise a redirect to UserProfile is returned.
The FirstConfigWiz module has a Login override mechanism. We could take advantage of it for UserProfile, too. 
However, what is the goal? Why an unprivileged user wants to see the Dashboard?