I submitted a case number: 553599
I was setting up our new install and was looking for an option to make Sub-Types optional when creating a ticket.
I'm thinking having a check-box on the parent or child to enable making a sub-type, if they exist, optional.
Sometimes we do a ticket as Break/Fix --> Desktop and won't go deeper, and other times we drill to Break/Fix --> Desktop --> Hardware.
It just depends on the need.