Hey,

it would be quite good to differ the settings of "assign ticket to role".

For example: Maybe someone don't want that reporter can assign tickets directly to one person, but want's to allow that users with role "xyz" could get implicite assigned by role.

This could be handy for some public ticketsystems.
If your company has 100 supporter and just 4 supportgroups, you don't want to let the user assign a ticket directly to one person. But maybe you want that the user could assign them to some usergroup.

Currently this could be done by a workaround.
assign to: -> read only (or later hide)
category: selectable -> implicite assigning to group
With this way, you could provide a group based assignment. But I think this could be more intuitive. :-)